KAREGIST.TPS should exist in the kirby alarm pro folder.
(in fact all of the files that kirby alarm uses are located in the kirby alarm pro folder)
I think the best thing to do will be to uninstall and reinstall kirby alarm pro.
(1) Exit kirby alarm by right clicking on the tray icon and selecting exit
(2) Make a copy of the existing kirby alarm pro folder (this is so we can recover your current alarms etc)
(3) Uninstall kirby alarm
(4) Use windows explorer to delete the kirby alarm pro folder
(5) Download and reinstall kirby alarm (I will send you a new rego code in a separate email)
Does kirby alarm pro start ok?
If so, reboot your computer and see if the error comes up anymore.
If all is ok then you can copy your old alarms etc from the backup folder by copying alarms.tps
(you will need to exit KA before doing the copy otherwise windows will complain the file is in use)
Hope this helps