that's because the switches aren't linked as they are in Looper Control mode. pressing Rec to stop the loop, while in Looper mode on the MFC, TURNS ON the Play switch. this is not happening outside of Looper mode.
the best way i've gotten that to work on the MFC is to use Switch Links for those 2 switches. "Switch Links" links multiple switches together. other controllers call this "grouping" buttons/switches. it makes it possible for only 1 switch of the group to be on at any given time. so this should solve most of the Play/Rec issues. after linking the Rec and Play switches, only 1 can be on at a time.
i show this briefly in my Looper video at 16:53:
Switch Links only work on switches on the MFC itself, not externals, if you wanted to go back to that.
in addition, you need to use the Play switch to play the loop when you are done recording. even after linking the switches with Switch Links, pressing the Rec switch to play the loop, the Play switch is off and needs to be hit 2x to stop the loop.
with Switch Links enabled:
press Rec to start recording
press Play to play (stop recording)
- this makes the Rec switch turn OFF due to Switch Links, and also turns the Play switch ON, meaning only 1 press to stop the loop
press Play to stop the loop
additionally you can turn the Immediate Play "OFF" in the Looper block. this means pressing the Rec switch a 2nd time while looping will store the loop and STOP, instead of immediately playing. this can be useful for recording a Chorus during its first pass, but then playing the verse immediately after - the Chorus recording is stored, then you can play it when the solo section comes up.
it's just the best way i figured out. maybe others have better ideas