I gues SET MARK option only puts a CHARACTER in the MENU BAR and u have to manually clean the other BAR to let it look like an "Option Menu".

More information...
I gues everybody here have tried using Windows Explorer, In the VIEW menu there is that 4 items, the Large Icons, Small Icons, List and Details, that when you to click to 1 of them it gets the small circle mark. I have tried this with VB using the CheckMenuRadioItem API in user32 and it works now im doing it in VFP but i cant let it work.