Yep that's what I tried, it didn't work (my screen shots in my latest post are me trying what you sent). Here's a video that further explains the potential problem:
11 days ago(+1)
You can try this one i removed the void parts and i also moved the walls a bit more on the middle
9 days ago(+1)
just sent a new update (v2.5) for the asset pack adding new walls tiles and hopefully making everything easier to tile , thanks for the suggestion