How to Isolate macros from different Workbooks?

[MV]

Hi,

I have an Excel Workbook that has Macros (both at Worksheet and module
levels) that in turn delegates most of the business logic to a VB6 COM
component.

OK, the problem is that when I have two different instances of this
workbook opened in the same PC, it seems that they are conflicting with one
another (I'm getting a lot of ActiveV instantiation problems).

I'm wondering what's the best way to 'isolate' this 2 Worbooks, should I
move all my module-level code to Worksheets?

Any ideas?

Thanks,
MV