Hello, and welcome to JustAnswer.com!My name is Jesse, and I'm here to help.
Just to confirm, this is a 4th generation iPod Touch?
It looks like Shadowgun Deadzone is currently broken, based on other online reviews and feedback. It's very likely that an update is in the works and will be out soon, but for now, there are a number of other people having the same issue as you.
I apologize that the game is broken, and wish there was a way around it, but it does look as it an update will be out soon.
I was hoping there was a way around this. Thanks.
No problem, sorry there isn't another way.