Well, if it works in the simulator but not the real hardware, then that's usually down to one of two causes:

1. The hardware is faulty;

2. You haven't fully simulated the hardware, or fully tested all possible scenarios, and there is some special case of real hardware events, timing, etc, which crashes your code.
An unexpected interrupt would be a good example.

Are you sure that you have handlers in for all interrupts - including the ones you're not actually using?

As you're using a Lite version of the simlator, are you sure that you're operating within all its stated restrictions?