I do not think there is a way around that issue.
You could use a table and at least get an inclusive list of all of the selected cells using Selection Start and Selection Size properties. But that does not fully fit the bill I would suspect.
The next idea would be to imbed an ActiveX control of an Excel spreadsheet. Then use activeX to get cell slections from Excel. I am only guessing that this is possible.
I will watch for any better ideas.
Ben