i have noticed a problem: whenever a belt has 2 different items, one on each lane, every single transfer to underground and to the surface again jumbles them up completely making the mod 100% unusable for belts with two different items on them. any setting i can adjust to keep the belt lanes separate while transitioning between surface layer and belt layer? using those 2 item belts a lot and i would still like to use the mod as well.

From the description:

Caveats

Items are mixed randomly in the left and right lanes of output belts. This makes Beltlayer only usable with belts carrying the same item in both lanes, or "sushi belt" designs that don't have any item placement requirements. This is a limitation of Factorio's loader entities.

The work around I do for this is to unsplit the belt before going down, run two lanes in the beltlayer undergound, one for each item, then on the otherside bring up both lanes and remerge the belt

Fixed in v2.0.0.

Thank you therax it totally works now! was my workaround helpful in fixing this?

The change was enabled by a new core feature in Factorio 1.1, the ability to link belts across surfaces.

nice! I wondered if that was what it was. just coincidence on timing then