Custom button issues - need help

I made a custom map with custom abilities that uses imported button artwork. The normal and passive buttons work fine, but for some reason, when the ability is either disabled, not researched, or the skill cannot not be learned yet, I get this green square for where the button is. Is there something wrong with this? Or am I doing something wrong?

Example

Art - Icon - Normal: (path)/PASBTNRagingFire.blp
Art - Icon - Learn: (path)/BTNRagingFire.blp

there is no where to edit the "disabled" field for the ability. Is there a way to fix this?

(How do I use the DISBTN(button name) icons anyway?)

The path for ANY disabled button is: ReplaceableTextures\CommandButtonsDisabled\DISyourbuttonname

in your case:
ReplaceableTextures\CommandButtonsDisabled\DISPASBTNRagingFire.blp
ReplaceableTextures\CommandButtonsDisabled\DISBTNRagingFire.blp

Just edit the original buttons to be darker and import them.