hand tracking makes unreal crash if no head tracking defined

[RalfRab]

Hello,

we defined the osvr server config, such that only /me/hands/right was defined but not /me/head and used ART tracking and VRPN.
When the unreal game is running and the hand target gets visible unreal is crashing. if /me/head is defined additionally all works fine.
Don't know, if this is something on OSVR side.

Best regards

RalfRab