xlights uses a formula to calculate large channel counts in a LOR sequence.
You have to put all your controllers in LOR unit order, which includes some HEX unit numbers ... and you cannot skip any unit numbers.
So it starts as 1,2,3,4,5,6,7,9, ... then goes to 0A, 0B, 0C, 0D, 0E, 0F, .... then goes to 10,11,12, ... etc ... up to 256 units in a universe ... so 256 LOR PC16 controllers to make a single pixelnet universe.
You can assign different LOR universes and then repeat the unit #'s again ... start back at 1,2,3 for the next universe, etc.
The confusing thing is people often incorrectly set it up as DMX or CCR on the LOR side ... when in fact its just set up as a bunch of LOR PC16 controllers.
The other problem people run into is skipping unit #'s or not starting with unit #1, or not using the hex unit #'s that LOR considers as part of the 256 valid unit #'s in LOR universe. A common mistakes is going from unit #9 to unit #10 ... instead of from #9 to #0A ...