Personally I think it's better to author structures in Teamcenter, not in Process Simulate.
Which objects did you create? A message like this sometimes happens when Teamcenter cannot understand the data provided by Process Simulate correctly.
TC Error 203341 means: Missing BOM Line.
I think if you've created a robot, Teamcenter does not understand in which structure to place it.
You can try to create Workarea to use it for Resource structure in Teamcenter. Assign this workarea to the process. Create new Resources under workarea, not as a root node in Process Simulate. Maybe it works.