You should be aware of what the demo version does if you exceed the 500 line limit.
It still runs the code, but turns every command after the 500th line to a G1 move to safe Z, this is a bit disconcerting if you happen to be in relative mode when it happens, since the head keeps moving up until it hits the top of the column or the stop.
Took me a month to bother upgrading, just check the end of your program and make sure it's what you expect before you run it.