Whoops! I may have spoken too quickly. Realized this morning the 'Add New' feature does come up with the update, but is essentially devoid of most of the normal features, e.g. the listing in the top right box of target stamp, small image, ability to right click and do searches, etc.
Shut down and rebooted but to no avail. Then went into the folder, renamed the 'update' StampManage.exe to StampManageUPDATE.exe, then renamed StampManageOLD.exe to StampManage.exe, restarted and all is well.
Think I will hold off on any updates for a bit.