[JD Mather]

The most common problem I see in a situation like this is a conflicting assembly constraint. Impossible to diagnose without sitting in front of the machine - but I would make a substantial wager that is the problem. You might be able to isolate it by removing parts or subs one-by-one. When I sit down to find a problem like this I can usually find the suspect part or assembly fairly quickly.

I would rate almost everything I see done in Inventor as garbage. Garbage in - garbage out. There is a real problem with professional level training.

If you can pack and go the assembly and send it to me I'll take a look. (be sure to preserve file/folder structure) jmather_at_pct_dot_edu