while testing mods and having lots(!!!) of mods on a map, i got several strange effects, one of them being that some logic circuitry didn't work as expected, and where a belt tile should measure the throughput suddenly items appeared. quite a while later while checking the long list of mods i finally found this mod and saw that i had cheated myself :-) LOL

then i had a closer look and again found some strange effects which might be related to some other conflicts between other mods, but maybe it is also related to how you enable the functionality of this mod? the effect is that items are only produced on belt tiles that i have placed manually (and sometimes also by bots?), but never on belt tiles that are automatically filled as soon as i place a blueprint (since it is a map for testing with lots(!!!) of mods i don't know yet which of the many mods gave me that ability and how to disable it again :-) nonetheless it is strange that your mod doesn't work equally on all belt tiles.

i also noticed that your mod has some interesting ability: it seems to place only that item which has the highest signal value, eg when the signals are 2 iron ore and 1 copper ore, it places iron ore, but with 2 copper and 1 iron it places copper, and with 2 iron and 2 copper it seems to obey the order of items in the craft window (placing iron since the order is ...-stone-iron-copper-uranium-...)
this ability could very nicely be used with an arithmetic combinator that negates its input and thus the type of items that is available least on a belt has the highest ("least negative") signal value and thus is automatically generated. too bad that to count the number of items i have to connect and read the belt tiles and thus will generate new items also on all those tiles that i use for counting items. but with one combinator per belt tile it should be possible to separate them from the signals and make it work :-)
edit 1: tried and couldn't make it work. a combinator can separate the belt from the "collected" signal, but the belt feeds the signal directly to itself and its input and output in this situation can't be separated. the output could be fed back to compensate, but not on the same tick and thus it remains a bit "glitchy" depending on how fast and well you implemented it (the better implemented, the more difficult to compensate).
edit 2: would it be possible for this mod to check whether a belt is set to "read belt contents" and then not generate new items on that belt tile? a similar problem for signals that enable/disable the belt can easily be avoided by only using virtual signals since no virtual items will be generated :-)

this ability might also be useful for a completely different application: colors! when i have red and green signals on a wire (for a lamp or whatever) currently a lamp will turn red since red always has higher priority than green. it would be nice if eg 5 red and 8 green would cause the lamp to light up green since 8>5. such a "max" function would also be useful in other cases that i didn't think of yet (maybe show the amount of items in a chest, using the item which appears most). but any such use should probably be another mod :-)