Hello,
Birds of NA is still supported and owned by thayerbirding.com.
V3.0 of Birder's Diary might run on Vista 64-bit. But v3.6 does in 9 out of 10 cases. (Vista 64-bit is the only combination that sometimes causes problems.) However, you can test this out quickly by simply downloading it from the Downloads page on this site, installing and running. I of course, would recommend upgrading to v3.6.
Instructions for moving BD from one system to another can be found in the Online Users Guide (Support => Online Users Guide) on this site. Then navigate to the How-To => Move Birder's Diary to a new Computer topic.
Let me know if I can assist further.
Jeff |