Completely uninstalled 3CX, rebooted the server, downloaded the BETA version again. Noted that it's 9Mb larger than the old one and the Update Module in 3CX reported that there were no new versions. Reinstalled the new download. Restored the backup, and everything works.
FYI - If it says there isn't an update, download the new version and compare the install files if you run into an issue and suspect you are running an older version.