I’m sorry if I am misunderstanding, but I just to clarify the repro steps:
- Create 2 BSP boxes
- Stack one on top of the other
- Create stairs high enough to jump on top
- Enable “Use Flat Base for Floor Checks”
- Climb up the stairs and jump onto the boxes
I’m unsure what you mean by, “now put the grid at 1 and make a curb/stair of 2 units in the grid(moving the top cube)”, I assume it’s step 3.