[fysiks]

My guess is that it will no longer know that it's a floating point value by not using PROB_ITEM_CHANCE strictly. Try applying the Float tag to array2D[][] where you're summing the values.

Also, when you say you tried something that doesn't work, you should provide that version of the code also so we can see what you tried and maybe fix it. It's hard to be sure what you actually tried when you describe it in words.