diff --git a/Engine/ac/dialog.cpp b/Engine/ac/dialog.cpp
index 9b9d79f74ed..00b970307d3 100644
--- a/Engine/ac/dialog.cpp
+++ b/Engine/ac/dialog.cpp
@@ -175,11 +175,39 @@ const char *Dialog_GetScriptName(ScriptDialog *sd)
 }
 
 //=============================================================================
+// dialog manager stuff
 
 #define RUN_DIALOG_STAY          -1
 #define RUN_DIALOG_STOP_DIALOG   -2
 #define RUN_DIALOG_GOTO_PREVIOUS -4
-// dialog manager stuff
+
+static int run_dialog_request(int parmtr)
+{
+    play.stop_dialog_at_end = DIALOG_RUNNING;
+    RuntimeScriptValue params[]{ parmtr };
+    RunScriptFunction(gameinst.get(), "dialog_request", 1, params);
+
+    if (play.stop_dialog_at_end == DIALOG_STOP)
+    {
+        play.stop_dialog_at_end = DIALOG_NONE;
+        return -2;
+    }
+    if (play.stop_dialog_at_end >= DIALOG_NEWTOPIC)
+    {
+        int tval = play.stop_dialog_at_end - DIALOG_NEWTOPIC;
+        play.stop_dialog_at_end = DIALOG_NONE;
+        return tval;
+    }
+    if (play.stop_dialog_at_end >= DIALOG_NEWROOM)
+    {
+        int roomnum = play.stop_dialog_at_end - DIALOG_NEWROOM;
+        play.stop_dialog_at_end = DIALOG_NONE;
+        NewRoom(roomnum);
+        return -2;
+    }
+    play.stop_dialog_at_end = DIALOG_NONE;
+    return -1;
+}
 
 void get_dialog_script_parameters(unsigned char* &script, unsigned short* param1, unsigned short* param2)
 {
@@ -1292,11 +1320,18 @@ struct DialogExec
     int DlgWas = -1;
     // CHECKME: this may be unnecessary, investigate later
     bool IsFirstEntry = true;
-    // nested dialogs "stack"
+    // Dialog topics history, used by "goto-previous" command
     std::stack<int> TopicHist;
     int ExecutedOption = -1; // option which is currently run (or -1)
     bool AreOptionsDisplayed = false; // if dialog options are displayed on screen
 
+    // A position in script saved by certain API function calls in "dialog_request" callback;
+    // used purely for error reporting when the script has 2+ calls to gamestate-changing
+    // functions such as StartDialog or ChangeRoom.
+    // FIXME: this is horrible, review this and make consistent with error reporting
+    // for regular calls in normal script.
+    ScriptPosition SavedDialogRequestScriptPos;
+
     DialogExec(int start_dlgnum) : DlgNum(start_dlgnum) {}
     int HandleDialogResult(int res);
     void Run();
@@ -1414,6 +1449,32 @@ void do_conversation(int dlgnum)
     dialogExec = {};
 }
 
+bool handle_state_change_in_dialog_request(const char *apiname, int dlgreq_retval, bool expect_dialog_request)
+{
+    // Test if we are inside a dialog state AND dialog_request callback
+    if ((dialogExec == nullptr) || (play.stop_dialog_at_end == DIALOG_NONE))
+    {
+        // Some command may only work inside dialog_request (?)
+        if (expect_dialog_request)
+            debug_script_warn("%s: not in a dialog_request(), ignored", apiname);
+        return false; // not handled, process command as normal
+    }
+
+    // Test if dialog result was not set yet
+    if (play.stop_dialog_at_end == DIALOG_RUNNING)
+    {
+        play.stop_dialog_at_end = dlgreq_retval;
+        get_script_position(dialogExec->SavedDialogRequestScriptPos);
+    }
+    else
+    {
+        debug_script_warn("!%s: more than one NewRoom/RunDialog/StopDialog requests within a dialog '%s' (%d), following one(s) will be ignored\n\tfirst was made in \"%s\", line %d",
+            apiname, game.dialogScriptNames[dialogExec->DlgNum].GetCStr(), dialogExec->DlgNum,
+            dialogExec->SavedDialogRequestScriptPos.Section.GetCStr(), dialogExec->SavedDialogRequestScriptPos.Line);
+    }
+    return true; // handled, state change will be taken care of by a dialog script
+}
+
 // end dialog manager
 
 
diff --git a/Engine/ac/dialog.h b/Engine/ac/dialog.h
index de66851b1f4..0788d3e0547 100644
--- a/Engine/ac/dialog.h
+++ b/Engine/ac/dialog.h
@@ -34,6 +34,10 @@ void do_conversation(int dlgnum);
 int show_dialog_options(int dlgnum, bool runGameLoopsInBackground);
 // Handles a dialog option, optionally "sais" its text, optionally run corresponding dialog script's entry
 int run_dialog_option(int dlgnum, int dialog_choice, int sayChosenOption, bool run_script);
+// Handles a game-state changing command (such as StartDialog) inside "dialog_request" callback.
+// Returns whether the change was handled in "dialog's way", and further processing is not necessary.
+// Otherwise should process the command as normal.
+bool handle_state_change_in_dialog_request(const char *apiname, int dlgreq_retval, bool expect_dialog_request = false);
 
 extern std::vector<ScriptDialog> scrDialog;
 extern std::vector<DialogTopic> dialog;
diff --git a/Engine/ac/gamestate.cpp b/Engine/ac/gamestate.cpp
index 3f328b0c4d3..ba0fa580ed9 100644
--- a/Engine/ac/gamestate.cpp
+++ b/Engine/ac/gamestate.cpp
@@ -531,7 +531,7 @@ void GamePlayState::ReadFromSavegame(Stream *in, GameDataVersion data_ver, GameS
     show_single_dialog_option = in->ReadInt32();
     keep_screen_during_instant_transition = in->ReadInt32();
     read_dialog_option_colour = in->ReadInt32();
-    stop_dialog_at_end = in->ReadInt32();
+    in->ReadInt32(); // was stop_dialog_at_end, which should not serialize
     speech_portrait_placement = in->ReadInt32();
     speech_portrait_x = in->ReadInt32();
     speech_portrait_y = in->ReadInt32();
@@ -726,7 +726,7 @@ void GamePlayState::WriteForSavegame(Stream *out) const
     out->WriteInt32(show_single_dialog_option);
     out->WriteInt32(keep_screen_during_instant_transition);
     out->WriteInt32(read_dialog_option_colour);
-    out->WriteInt32(stop_dialog_at_end);
+    out->WriteInt32(0); // was stop_dialog_at_end, which should not serialize
     out->WriteInt32(speech_portrait_placement);
     out->WriteInt32(speech_portrait_x);
     out->WriteInt32(speech_portrait_y);
diff --git a/Engine/ac/gamestate.h b/Engine/ac/gamestate.h
index e8301f2c308..08ffc3bc30f 100644
--- a/Engine/ac/gamestate.h
+++ b/Engine/ac/gamestate.h
@@ -173,6 +173,10 @@ struct GamePlayState
     int  show_single_dialog_option = 0;
     int  keep_screen_during_instant_transition = 0;
     int  read_dialog_option_colour = 0;
+    // stop_dialog_at_end - special value that is not supposed to be used in user script,
+    // but used in a generated dialogscript (when converted from dialog script slang)
+    // to tell how to proceed after "run-script" command ("dialog_request" callback).
+    // if non-0 - means that we are inside "dialog_request" callback.
     int  stop_dialog_at_end = 0;
     int  speech_portrait_placement = 0; // speech portrait placement mode (automatic/custom)
     int  speech_portrait_x = 0; // a speech portrait x offset from corresponding screen side
diff --git a/Engine/ac/global_dialog.cpp b/Engine/ac/global_dialog.cpp
index d07ca68357d..9d28c9d8098 100644
--- a/Engine/ac/global_dialog.cpp
+++ b/Engine/ac/global_dialog.cpp
@@ -27,23 +27,15 @@ using namespace AGS::Common;
 
 extern GameSetupStruct game;
 
-ScriptPosition last_in_dialog_request_script_pos;
-void RunDialog(int tum) {
+void RunDialog(int tum)
+{
     if ((tum<0) | (tum>=game.numdialog))
         quit("!RunDialog: invalid topic number specified");
 
     can_run_delayed_command();
 
-    if (play.stop_dialog_at_end != DIALOG_NONE) {
-        if (play.stop_dialog_at_end == DIALOG_RUNNING)
-            play.stop_dialog_at_end = DIALOG_NEWTOPIC + tum;
-        else
-            quitprintf("!RunDialog: two NewRoom/RunDialog/StopDialog requests within dialog; last was called in \"%s\", line %d",
-                        last_in_dialog_request_script_pos.Section.GetCStr(), last_in_dialog_request_script_pos.Line);
-        return;
-    }
-
-    get_script_position(last_in_dialog_request_script_pos);
+    if (handle_state_change_in_dialog_request("RunDialog", DIALOG_NEWTOPIC + tum))
+        return; // handled
 
     if (inside_script) 
         get_executingscript()->QueueAction(PostScriptAction(ePSARunDialog, tum, "RunDialog"));
@@ -51,15 +43,9 @@ void RunDialog(int tum) {
         do_conversation(tum);
 }
 
-
-void StopDialog() {
-  if (play.stop_dialog_at_end == DIALOG_NONE) {
-    debug_script_warn("StopDialog called, but was not in a dialog");
-    debug_script_log("StopDialog called but no dialog");
-    return;
-  }
-  get_script_position(last_in_dialog_request_script_pos);
-  play.stop_dialog_at_end = DIALOG_STOP;
+void StopDialog()
+{
+    handle_state_change_in_dialog_request("StopDialog", DIALOG_STOP, true);
 }
 
 void SetDialogOption(int dlg, int opt, int onoroff, bool dlg_script)
diff --git a/Engine/ac/global_room.cpp b/Engine/ac/global_room.cpp
index caadec7325a..d3e037230c0 100644
--- a/Engine/ac/global_room.cpp
+++ b/Engine/ac/global_room.cpp
@@ -15,6 +15,7 @@
 #include "ac/common.h"
 #include "ac/character.h"
 #include "ac/characterinfo.h"
+#include "ac/dialog.h"
 #include "ac/draw.h"
 #include "ac/event.h"
 #include "ac/gamesetupstruct.h"
@@ -68,7 +69,6 @@ void SetAmbientLightLevel(int light_level)
     play.rtint_light = light_level;
 }
 
-extern ScriptPosition last_in_dialog_request_script_pos;
 void NewRoom(int nrnum) {
     if (nrnum < 0)
         quitprintf("!NewRoom: room change requested to invalid room number %d.", nrnum);
@@ -85,17 +85,8 @@ void NewRoom(int nrnum) {
 
     can_run_delayed_command();
 
-    if (play.stop_dialog_at_end != DIALOG_NONE) {
-        if (play.stop_dialog_at_end == DIALOG_RUNNING)
-            play.stop_dialog_at_end = DIALOG_NEWROOM + nrnum;
-        else {
-            quitprintf("!NewRoom: two NewRoom/RunDialog/StopDialog requests within dialog; last was called in \"%s\", line %d",
-                last_in_dialog_request_script_pos.Section.GetCStr(), last_in_dialog_request_script_pos.Line);
-        }
-        return;
-    }
-
-    get_script_position(last_in_dialog_request_script_pos);
+    if (handle_state_change_in_dialog_request("NewRoom", DIALOG_NEWROOM + nrnum))
+        return; // handled
 
     if (in_leaves_screen >= 0) {
         // NewRoom called from the Player Leaves Screen event -- just
diff --git a/Engine/ac/runtime_defines.h b/Engine/ac/runtime_defines.h
index 986bf54b449..859866ccf29 100644
--- a/Engine/ac/runtime_defines.h
+++ b/Engine/ac/runtime_defines.h
@@ -30,11 +30,6 @@
 #define MAXGSVALUES 500
 #define MAXGLOBALSTRINGS 51
 #define MAX_INVORDER 500
-#define DIALOG_NONE      0
-#define DIALOG_RUNNING   1
-#define DIALOG_STOP      2
-#define DIALOG_NEWROOM   100
-#define DIALOG_NEWTOPIC  12000
 #define MAX_TIMERS       21
 #define MAX_PARSED_WORDS 15
 
@@ -122,10 +117,19 @@ const int LegacyRoomVolumeFactor            = 30;
 // a 1-based movelist index offset for characters
 #define CHMLSOFFS (1 + MAX_ROOM_OBJECTS)
 #define MAX_SCRIPT_AT_ONCE 10
+
 #define EVENT_NONE       0
 #define EVENT_INPROGRESS 1
 #define EVENT_CLAIMED    2
 
+// Values for GameState::stop_dialog_at_end;
+// tell what to do with the current Dialog after returning from the option script
+#define DIALOG_NONE      0
+#define DIALOG_RUNNING   1
+#define DIALOG_STOP      2
+#define DIALOG_NEWROOM   100
+#define DIALOG_NEWTOPIC  12000
+
 // Internal skip style flags, for speech/display, wait;
 // theoretically correspond to InputType in script (with a 24-bit shift)
 #define SKIP_NONE       0x00
diff --git a/Engine/debug/debugger.h b/Engine/debug/debugger.h
index f12d06360e1..bb56a75f64d 100644
--- a/Engine/debug/debugger.h
+++ b/Engine/debug/debugger.h
@@ -29,8 +29,6 @@ extern int break_on_next_script_step;
 int check_for_messages_from_debugger();
 bool send_state_to_debugger(const char *msg);
 bool send_exception_to_debugger(const char *qmsg);
-// Returns current script's location and callstack
-AGS::Common::String get_cur_script(int numberOfLinesOfCallStack);
 bool get_script_position(ScriptPosition &script_pos);
 
 void check_debug_keys();
diff --git a/Engine/script/script.cpp b/Engine/script/script.cpp
index a452cd031d8..587588a3c57 100644
--- a/Engine/script/script.cpp
+++ b/Engine/script/script.cpp
@@ -89,30 +89,6 @@ size_t numScriptModules = 0;
 static bool DoRunScriptFuncCantBlock(ccInstance *sci, NonBlockingScriptFunction* funcToRun, bool hasTheFunc);
 
 
-int run_dialog_request (int parmtr) {
-    play.stop_dialog_at_end = DIALOG_RUNNING;
-    RuntimeScriptValue params[]{ parmtr };
-    RunScriptFunction(gameinst.get(), "dialog_request", 1, params);
-
-    if (play.stop_dialog_at_end == DIALOG_STOP) {
-        play.stop_dialog_at_end = DIALOG_NONE;
-        return -2;
-    }
-    if (play.stop_dialog_at_end >= DIALOG_NEWTOPIC) {
-        int tval = play.stop_dialog_at_end - DIALOG_NEWTOPIC;
-        play.stop_dialog_at_end = DIALOG_NONE;
-        return tval;
-    }
-    if (play.stop_dialog_at_end >= DIALOG_NEWROOM) {
-        int roomnum = play.stop_dialog_at_end - DIALOG_NEWROOM;
-        play.stop_dialog_at_end = DIALOG_NONE;
-        NewRoom(roomnum);
-        return -2;
-    }
-    play.stop_dialog_at_end = DIALOG_NONE;
-    return -1;
-}
-
 void run_function_on_non_blocking_thread(NonBlockingScriptFunction* funcToRun) {
 
     update_script_mouse_coords();
diff --git a/Engine/script/script.h b/Engine/script/script.h
index 9fa085befc4..a88296b82f3 100644
--- a/Engine/script/script.h
+++ b/Engine/script/script.h
@@ -93,7 +93,6 @@ struct NonBlockingScriptFunction
     }
 };
 
-int     run_dialog_request (int parmtr);
 void    run_function_on_non_blocking_thread(NonBlockingScriptFunction* funcToRun);
 
 // TODO: run_interaction_event() and run_interaction_script()