The latest version of FPV Air Tracks has had some bugs that will cause crashing when playing multiplayer, these crashes are caused by some outdated third-party code used to read in controller input to the game.
We are replacing this with the newly released equivalent made by Epic Games but currently Epic have not made thier Raw Input plugin work with 32bit builds, so we will not be supporting 32bit platforms untill Epic fix this bug and we are able to upload a new builds supporting both architectures.
I hope this doesn't cause too much distress and that Epic games will fix the bug soon.