i thought that easiest way to import models is to use .3ds files due to many 3ds import tutorials,and everything was ok but when i tried to fix texture coordinats with UVWunwrap modifier everything seems so inverted.in max i had one situation in viewports and when i import that model into opengl app and texture coordinats seemed inverted.that much complicates the whole thing....and i can just cant get it right...

I had the same problem with milkshape tex coordinates. An easy solution is to play around with the texture matrix.