Draw 4 parts. Make a sub-assembly with the first two parts. Make a main assembly with, the sub-assembly and the remaining two parts. Make a drawing from the main assembly using standard 3 views Auto balloon the top view. Try to auto ballon right view, nothing! Auto balloon right view with ignore multiple instances box cleared, only two balloons on right view!!!
Now add a second sheet Insert standard 3 views. Try to auto balloon any view, nothing. Auto balloon any of the views with ignore multiple instances box cleared, only two balloons on any view!!!
OK, now insert BOM on sheet one, selecting top items only. Now change to second sheet. Insert BOM, using parts only. Change BOM to top items only. Balloons do not change to match BOM. Now do the same to sheet one BOM. If I have this correct, changing sheet one BOM, updates balloons on sheet two and changing sheet two BOM changes the balloons on sheet one!!! If your's do not do this , change the BOM's a couple of times and it will... oooherrr???