OK, I took the liberty to clean it up a bit with some suggestions:
(1) Allow user to operate tab in case corrections are needed (hide the tabs if this is not desired).
(2) Only one set of OK and cancel buttons are needed, they can be outside the tab. Cancel stops the VI. OK goes to page 2 or stops the VI if already on page 2.
(3) We don't need a big case structure, just a single event structure.
(4) You can use a filter event for key-down, but make sure that "discard?" gets the appropriate boolean depending on the tab state so typed charaters are not lost.
Of course programming styles vary, so modify as needed.
🙂