Single-axis "FixedPositionX/Y" object

[TylerMcBride]

The FixedPosition object is great, but it restricts BOTH axes when I really want to make a platform that only moves up and down, for example (when the player touches it, it can slide left or right from their movements).

Can we get FixedPositionX and FixedPositionY objects to fix this problem? Or some way to only enable one axis at a time?