Something About Negative Values...

Are some fields of item abilities unable to reverse in use? Because, I have a Movement Speed -50 on an item and it doesn't work, strangely. I checked for the negative values on check in Preferences AND held Shift+Enter when putting in the negative numbers in the field, but my efforts proved useless. Clearly, negative values don't work for everything(duration, AOE, etc.), but I was sure that Item abilities are an exception.

I was pretty sure that auras could reverse, too. I have a reverse Devotion Aura and it doesn't work. I even made it -50 armor and it still didn't work. I've used reversed auras for quite a long time now and they SHOULD work. Is something wrong here or is it just me?

Hero stat bonuses cannot be negative, I know that, but devotion aura can (99.5% sure).