Hmmm, I couldn't reproduce this, from the screenshots it seems you were issuing move commands, and the code paths to the crashes support this, coming via Commander::giveDefaultOrders().
Code in there has been updated for load & unload though, which I 'suspect' you are using. So if it's not to much of a pain, could you package it up for me, deleting all models and textures, so I can play with the same setup. I'm happy to play it with pink boxes