Unfortunately, the eco sunrays and aurora borealis are completly broken at the moment and cause severe lag. That's why I finally decided to completely disable those effects.
These stairs are objects though and do not auto-adjust their height to match the wall height, so only the shortest wall height is currently visually supported, but sims can still use the stairs to travel to the next floor without issue.
Now introducing my Sims 4 preteen mod! First of all the teens in this game look too grown. Sims go from a little kid to looking like they pay taxes. So that's why I created this mod to give us a good in-between phase.