For months my NOW TV app on my Asus laptop windows 10 has not been working.
After deleting files and uninstalling, reinstalling the app multiple times, changing from Chrome to Microsoft Edge. I was getting super frustrated and thought there was no solution. Nothing was working. I was in the Now community and people were saying that deleting a roaming 'cisco' file would work, which didn't.
Finally today I've found the problem and solution. It was my Bit Defender Anti-virus protection that was preventing the pop-up player. Annoying that it's something so simple, and I'd overlooked.
But happy it's resolved now.
Posting in case others might have a similar issue with a crashing Now TV player.
Check your Anti-virus software and see if that's what's causing the player to crash!