Attached Link: UV mapper

This is just a guess but Bryce has a limit of 511 parts/groups per import. I don't have Max but I'd guess that what may need to be done is to "weld" the object so that there are fewer parts. You can check on this by loading the .OBJ into Classic UVMapper (free, link). In the Selection menu is an item for both mesh and material groups and if you find you have hundreds listed then that's probably the problem. UVMapper will also attemp to correct any non-standard syntax in the file and often loading the .obj into it and turning right back around and saving it under a new name will fix the Bryce import problem. UVMapper will also report on any "fatal" errors that it finds. Again, this is real guess 'cause the bad i/o errors relates to a lot of different problems.