Can I migrate additional data after I've done it once?

[JoanHall]

I installed VM2 (in a subdirectory) and migrated everything over from my VM1 site.  After the migration, I discovered that I needed to get an additional package to be able to sell my downloads.  It took me some time (over a month) to get all of that working on the VM2.  Meanwhile, the VM1 was still live and doing business.

The VM2 site is finished now and I've switched them over so the VM2 is now the live one.  But it doesn't have the information for the new customers and new orders that came through the VM1 site during the month since I did the migration.

I tried just redoing the migration, but it didn't work (I suppose the reason it didn't work is because the VM1 data is now in a subdirectory instead of being in the live location?).

How can I add last month's orders and new customers to the VM2 data?