Are you looking at the online Help within UFT or looking in the FAQs on the UFT Web site? Here is what the online Help in UFT says about your problem:
The OK and Express buttons in the Add Event window will be dim if a default principal is not marked for events in the Role Template window.This occurs when using ROOTS IV library files created in Version 1.0 which were not updated with version 1.1 of ROOTS IV.To update the library files and correct this problem, follow these steps:
1.From the Utilities menu, choose Project and then Check.
2.Check the options for updating event libraries:Add New Event/Role Types and Replace Missing Event/Role.
3.Do not check any other options in the Check window and then choose OK.
This process will only update events and roles supplied by Ultimate Family Tree.If you have any user defined events or other event types imported from GEDCOM or ROOTS III, the default principal must be marked manually using the Role Template window.