It looks like you are trying to "pop pointer 1" with a value of 12 on the top of the stack.
You are a long way into initialization. The supplied Sys,init calls
do Math.init(); // Array.new(16), twice
do Screen.init(); // Array.new(17)
let buffer = String.new(6);
do Output.initMap(); // Array.new(127) and 127 of Array.new(11) creating the font
do Output.createShiftedMap(); // Array.new(127) and 127 of Array.new(11) creating font chars << 8
Thanks Mark, there must be something wrong with my alloc/deAlloc then. Would you mind taking a look at my code? I've been staring at it for the last two hours and couldn't quite figure out what's wrong.