"math operation" forgets operands

In the map editor, the "math operation" action has places where you can give it a number, or point it to a variable that you've created.  However, if you type in a number instead of using a variable, it just forgets and reverts to 0.  That is why my Mandalf map that I keep uploading has a variable that's just "1".  If you try to do a math operation and type in 1, all you have to do is click on a different script and then back again and it's already gone back to 0.