I have a cynose KB and a really expensive wireless mouse from this company, and the KB never lights up / but the mouse works on it’s own on an M1 Mac in Sonoma, or elsewhere in my all Apple Lab. Nope on the KB.

I installed synapse, had to go thru several updates to get it say all is good.  Then log in again and again, then restart, and finally everything is good but the devices never shows!