[quote user="BFrancis"] I don't know if my Excel call is making this issue[/quote]
That statement is ambiguous: are you calling Excel VBA from MicroStation VBA, or are you calling MicroStation VBA from Excel VBA?
Either way, you are working out-of-process. That is to say, MicroStation is one Windows process and Excel is another Windows process. When you call across a process boundary, you raise all kinds of potential hazards. VBA, on the whole, does a good job of hiding the complexities of inter-process communication. However, that apparent simplicity masks a lot of hidden activity. It's l ike a swan swiming on a lake: on the surface, everything is serene and elegant; but, beneath the water, the paddles are working furiously to keep the bird in motion.
MicroStation VBA has comments about out-of-process code. Read carefully what it has to tell you.