Managed to fix it by loading the game without the OLDD folder, then adding it back it when in-game and reloading all parts from the debug menu on the KSC main screen. Not sure why it's doing this, but this workaround seemed to fix the problem. EDIT: You'll need to do the above for every game start. This is bit annoying if the game crashes 1/2 way to the moon, as the reload will cause your mission to be deleted due to missing parts. @DennyTX, do you have any idea what's causing this bug / can you take a look? Btw, AMAZING mod otherwise!!! I'm a big fan of recreating historic missions and your work here is brilliant.