Apologies if this is a repeat, I only read through 3 pages of open issues.

The other player on my local server connecting from outside my network can't stand on platforms. I've built an elevator on a pully up a cliff and her player character goes through going down or up. She also fell through my advanced piston door that sinks into the floor while it was open. I can see it happening, so it isn't network lag or very big network lag causing it. Are there permissions that prevent proper entity behavior?

I only recently started the server back up and updated forge and create to the recommended and latest versions (36.1.00 for forge, 0.3.1c for Create). She was able to collide with platforms perfectly fine before these updates in Create version 1.16.3+ v0.3c.

Thanks, again, sorry if this is a repeat report :)

Nice, thanks!

Afaik that's an issue with optifine, tell her to switch to optifine G6/remove it entirely and see if that fixes it