Found it...
I had the CHECKIT, but not the MENUTOGGLE...
Added that, and it is working as expected... (Not the whole program, just the menus, but it is progress!!)
Code:
{ &item13, 0, 0, 150, 12, ITEMTEXT|ITEMENABLED|CHECKIT|CHECKED|MENUTOGGLE|COMMSEQ|HIGHCOMP, 0, (APTR) &text14, NULL, 'S', NULL, 0 };