For 1 and 2 the Maya Bonus Tools has scripts that sort of do this. For 1 you can select a bunch of objects and randomize translations on the X axis. For 2 there is a placement tool and a simple orient to face tool and probably a bunch of others you could checkout. I;m not sure what you're asking in 3, and don't know the…
2. Modify>Snap Together Tool.. click your faces then hit enter. also, in your bush terrain example specifically, google up the 'Modify>Paint Scripts Tool', you can paint your bushes onto terrain. 4. Modify>Replace Objects. replaces all selected objects with the last selected object. 6. Modify>Convert>Instance to Object
Thanks for helping me. I added the solutions to the main post. Thanks haiddasalami & m4dcow. but i like to avoid scripts a mutch as posible, because in a few weeks time i'm going to work in a company that uses maya. and thay all use pretty mutch the same settings. If some one can still help me with 1, 2, 3a and 5 that…