3. this option is necessary to enable communication between wireless clients inside their (with a capsmans acl) assigned vlans, so i have to enable it.
Now I get it: it's not really a bridge, but rather ap - station, when the far end of the bridge is among some other "regular" clients.
1. because it seems like a bridge, wich is configured in station bridge mode, doesnt seem to connect with my capsman managed network (to be able to connect i think both sides need to support station bridge mode an since capsman doesnt support it, my caps also dont and so the bridge is not able to connect with my infrastructure)
2. exactly right, but it just doesnt connect in this mode
That should work if AP is in AP-bridge mode, and station is in station-bridge mode.
Probably it doesn't want to connect for some different reason?
Two things to try for a possible workaround:
1) If printer is the only device behind the bridge you can try mode=station.
2) You can try creating a virtual interface on the AP that will work in mode=bridge and connect to it in mode=station-bridge (but I don't remember wether is it possible to control virtual APs independently if the master is controlled by capsman).