game: 1.21.1
mod: 2.0.2
neoforge: 21.1.72

It just can't either receive or send source from/to ars like it did in 1.20

Works fine in dev. Do you have a setup that can be reproduced? Does the network containing the ME Source Jar include any source storage cells at all on any chests/drives?

I am having an issue where sourcelinks will not deposit into ME Source Jar, nor imbuement chamber pulling from one.

Source jar and system are powered by system, they are online and there is a source cell in the drive to the right

I'm having the same issue in ATM9 to the sky modpack (1.20.1)

I have a source cell in my system but the source only gets sucks out of the jar and then its gone. (Both the normal jar and the me one)

is there no wiki where it describes what the set-up should look like?

Not yet, unfortunately. I am but one lone dev and I'm spread thin enough already across multiple projects.

Just to clear it up, however: all the ME Source Jar does is act as a proxy for all the Source stored on an ME network and exposes that stored source as though it were contained in a regular Source jar. So far the only testing I was able to carry out myself is that it is possible to move source into and out of it using a Source Relay and Dominion Wand, but I might have to double check if it works properly with things like the Imbuement Chamber and Enchanting Apparatus.

got it to work somehow.
Disconnected everything and reconnected it now it works... I have no clue what I did different

The ME Source Jar only works for relays for me. So for my Enchanting Apparatus I have a relay to a normal Source Jar. Same for the input.

now that it is working for me it pulls from my collecting ME Source to my system but only when connected right, on some sides its not pulling. (without any export or import buses)
and then it pushes it into other ME Source jars on the network.
I will update and post a picture when I get the time.

I also have this problem on ATM10. I can only use the source link to other jar for the enchanting and the charger

I neglected to post anything about this, but the problem has been known for some time now and it's because of Ars Nouveau itself hard-coding much of its Source transfer-related operation to its own Source Jar only rather than any external add-on's potential Source containers.

This issue will remain open until it is resolved upstream—likely quite soon at this point—but for now there isn't really anything I can do from Ars Énergistique's end. I can only apologise.

So source cell works great, the only problem so far that ME source jar just dumps everything to interfaces acros AE system, and storage bus from jar just breaks it. So its kinda unusable if you have interfaces in system, i wish storage bus would work on it so you can setup a proper storage pulling on demand