Hi, I'm Chuzhoi. Sorry for confusion with the nicknames. Half a year ago Shadowhide asked someone to make a model of a moving train for his mission, and I agreed to help. You can see the result now. Actually, it's still a draft, which is very far from completion. Unfortunately, I have too little time for mapping and modelling at the moment, so it's done very slow. I don't know if Shadowhide will make a mission from all this (and it seems he doesn't know). But I liked the idea and I intend to make a mission myself. Thanks for your comments. Here are some answers for your questions: The terrain consists of fragments, generated in a random order with the help of a script. Actually, the order is not 100% free - each fragment type can be followed by 2-3 other fragment types. For example, the fragment named 'terrain_left_ab' can be followed by fragments named 'terrain_left_ba', 'terrain_left_bb', and 'terrain_left_bc', selected randomly. The trees are grouped in small groves consisting of 3-10 trees for increasing performance (each grove is a single model, not group of models). Doom3 in not the 1st engine in which I use this trick. Real couplers also don't seem to hold anything. However, one can suppose that there is some sort of a lock, located completely inside the coupler. As for me, I'm very pressed for time at the moment. Sorry. PS. Another my work of the last year - http://www.ttlg.com/...ad.php?t=138298