Uncertain Title

Thank you all for the tips, they all helped me narrow down the issue. Turns out I had accidentally adjusted some walls and it caused the visleafs to not be completely separated from each other.

I have a small room that I split almost completely in half using a "wall" (brush). I cloned a wall of the sealing brush and dragged it to the small opening, cut a hole into it, and turned it into a visportal. Yet for some reason, the portal gets dropped at runtime. It's puzzled me for the past couple hours, and I can't quite understand why it won't work. Here is a rough picture of what I am trying to make. The red lines are entryways, while the pink is the portal I am trying to make.

I will be referencing this a lot, thanks for the info! I didn't even think about checking for brush textures! The No-Draw Carpet brush was exactly what I needed ^ ^ After sleeving all the stairs in brushes for around 45 min, this idea dawned on me...and then I saw your response. I should have double checked all the responses Dx Thank you all very much for the feedback, this was all exactly what I needed and more ^ ^

Hello! I am pretty new to Dark Radiant, and as the title suggests, I am having issues with stairs. The player is capable of vaulting over large walls, but no matter what model of stairs I use, they struggle to ascend even the smallest staircase. Is there an explanation for this, or even a tutorial on how to implement them?