I need to merge an install on another machine with the install on my primary.  I really do not want to lose my history on the second machine.  Any suggestions?

Keeping the install folders separate...
EXPORT that version. AND IMPORT into the new "merged".
For backup, keep the DAT files in an archive before/after until you check the merged data.

I have two installs where I would like to import all transfers from install2 into install1, merging the the two.  I used the export feature on install2, unchecking all options but the transfers.  I then import the resulting file into install1, but it doesn't merge, it removes all existing transfers in install1.