Can't access settings on Verizon Galaxy S4 with Straight Talk SIM?

[AC Question]

I changed over to Straight Talk today with my Galaxy S4 that I've been using since I got it with Verizon. My number ported over to the AT&T SIM that I decided to use and everything works great. There's just one huge problem. I need to change my APN, which would be easy peasy if I could actually open Settings on my phone. Every time I try to open Settings on my phone (whether through the menu button from the home screen or the application shortcut) it opens and immediately closes. If I put the Verizon SIM back in this behavior stops. Has Verizon come up with a sneaky, underhanded way of discouraging people from taking their phones to other carriers, and if so is there a work around?