Hi Christian,
if it crashes while migrating a certain Workbook, I would tend to believe that the Workbook is having a query with a lot of data in it (is it?). In this case having office 64-bit and Analysis 64-bit would help you.
Else there is no progress bar, what you see is what you get. Anyway, soon there is going to be a nice service coming out from SAP Consulting around this topic...
Cheers
Victor