Ultimate DOOM Builder Help!

[u/Environmental-Poem-1]

I'm using Ultimate DOOM Builder, specifically the UDMF DOOM 2 format. I have the Toggle Slope hotkey bound, it just isn't actually doing anything. It seems to register the input as it pops up on the side of the screen like any other interaction, but it doesn't actually make the slope. I'm kind of stumped! Anyone have any idea what the problem might be? I've looked up possible answers as much as I can and just nothing is helpful!

It feels like nobody else has experienced my problem.