As far as I can tell, the main problem is that you've got numbers that are too big (uBasic numeric literals are limited to 6 digits, though I'm not sure that's documented anywhere outside the code). So your 2520000 is too long. You can rewrite it as 252*10000 and it should be OK.
Unfortunately the uBasic interpreter, when scanning for a label to jump to, hits the overlarge numbers and instead of stopping at the error, it loops. My uBasic debugger does the same thing (I guess I ought to fix it!).
