Hello,
When using Factorissimo2 with Ultimate Belts (https://mods.factorio.com/mod/UltimateBelts) , I faced with the problem that not all conveyors work when entering the building.
Most likely this is due to the restriction on incoming items.
Can you add support for this mod?

I can confirm that when upgrading to the belts above blue that is provided by this mod.
You basically end up with "burps" if you upgrade the belts on both inside and outside to any tier above blue.
What you will notice is that there will be no product flowing, 2-3 seconds later you get a quick "burp" of items and then it stops again for 2-3 seconds and this cycle repeats.

would love to see some support for this mod too

Yes，This BUG also with Bob‘s Mod，please fix it. thank you~