WC3 editor gameplay constants

Hello! I’ve been working a lot on my 4 player coop campaign map since I learned how to add custom models for heroes. I’m currently going through gameplay constants. It seems for “Movement - Units Speed - Minimum” whenever I try to reset this by clicking reset value it won’t save, it just sets it to forced value 0 when I open gameplay constants again. Anyone know why? I’ve checked “Use custom gameplay constants” but I’m not sure if unchecking it will break the other constants I’ve manually set.