Large generated schematics generating rendering fails

[Dushess]

Description of Issue:

When you imported that in your world and trying to look at it from above it might and shortly will skip chunks on loading phase. In result you will see your creation with miltiple full-height holes. Raising camera above precision rendering point (to trigger simplifying textures) and going back can fix that, but it will start again. Probably if you gonna do it 10-20-whatever times, it will be fully loaded. But anything nearby (same imported areas) will act same. Looks like memory-on-loading-chunks issue or saved-chunks issue. Also already rendered chunks after climbing always will disappear and be rendered in simple mode again. Most of them is good with normal view. Also that starts mostly far from starting position (after map is opened in editor). (rarely it just becomes stuck and wont render anything more with normal textures)

MCEdit Version:

1.5.6.0 and pre1.6.0.53

Minecraft Version the world was last opened in:

1.12.2

Operating System:

Win 7 x64

A screenshot or full text of the error from the console:

How to reproduce:

Generate large schematic from common mesh (obj or something) via poly2vox.exe + aux filter for MCEdit, import it into any existing world and start to look whole affected area from above.

[Dushess]

Any help? I can't work here with this bug...

[Dushess]

Unstable, but semi-working, will close for now.

[Dushess]

So, it is consistent on latest, mostly on no-chunks-area where I placing parts. Often goes stuck completely after 10 оr something minutes of work. Might go on another test runs but all basic info is here already.

[Dushess]

Any idea?