This is really strange.
“Reverting to 1.34” = the 1.34 firmware from the MSW site?
This is hard to diagnose for me: I don’t have an MSW-manufactured 16n, just OG ones I built myself. I’ve tested this firmware with other users of MSW 134LC boards, too, and haven’t been able to reproduce that.
If Max “can see it” - you mean over USB-MIDI? If so, what channel/cc combination is fader 1 spitting out - and then, in the editor, is that what the editor is expecting? If there’s a discrepancy, you could user the editor to alter the channel of fader 1, zap the new config over, and then reset it to whatever you want. There could have been an issue with the new firmware setting its “factory defaults”. Seems unlikely, but “not moving a box in the editor” vs “not actually sending any data” are not the same issue, and I’m trying to work out which you mean, given Max has got some data somehow. It could, after all, be a bug in the editor.