Add/Remove Attribute?

I can't seem to get add/remove attribute to work..are there any known bugs with it?

Basically I want my player (using platform behavior) to either be able, or not be able to collide with certain objects depending on conditions. Is there another way of doing this besides removing attribute or changing collisions to none?

While you can add Attributes at runtime, removing them does not work. If you are using Platform movement setting to the collision mask to none would be the only option. Unless you maually make a platform movement with custom movement, then you'd have more control over collisions.