I think your only shot is via holding the 2 mouse buttons and booting without startup-sequence then.
Do you not have login at Hyperion to download OS 4 updates? Isn't one of the updates an ISO?
I guess if WordWorth updated files that it shouldn't have, it will be in either C: or LIBS:. So maybe you can copy the contents from one folder to another in the DOS prompt then.
By the way: I created a second boot partition on my system called Workbench Backup with a lower boot priority. As soon as something happens to my main partition I go into the early startup sequence and disable the main partition so the backup partition then boots.