I have a 22 XL STX FX2. My Fordpass app works like 99.9% of the time. There was a short period in December/January (of course the coldest months) where it didn't work some mornings. Usually I would restart my phone and it solved the issue, most times. It's been working everytime for awhile now. I think it's a really cool feature especially considering my last vehicle was made in the last century, lol. I just chalk it up to digital gremlins. It's amazing that something like this even exists and works at all. I suppose I'm getting old and I have a child like wonder of any and all futuristic tech. It's hard for me to complain when my last truck had crank down windows and I'm old enough to remember life before the Atari 2600, much less the internet.
Unfortunately, I do not have the remote start key fob but like I said, I'm happy with this tech even if it doesn't work every once in awhile.
Good luck folks. I sure do LOVE my truck!