The cruise thing must be sporadic.
I know what you guys are talking about and mine has done the same thing.
However, last night I tried it after reading this thread yesterday and last night mine worked as designed.
Set my cruise at 75mph. Hit my brakes, slowed down to 65mph, then pushed up to RESUME, it worked.
Set my cruise at 75mph. Pulled back on the CANCEL button, slowed down to 65mph, the pushed up to RESUME, it worked.
Later in the evening, after I hit my brakes and came to a complete stop, then tried to push up to RESUME, it didn't.
None of the times did I actually turn the cruise off, the light was always on displaying in the dash.
Maybe it has a mind of its own.
I did discover something else though last night that bothered me, check out this thread and try it.
Fan & Defrost/Lower