Great!
Now, my setup would be with the wired switches that are already installed, and I would use FTS14KS instead of FAM14.
In a different topic (EnOcean 2: FGW14-USB supported - #59 by dirkdirk), I read flysl88 has managed to set up his system with a FTS14KS. I’ll try asking him how that worked exactly. 
This project is moving slowly, as it’s a bit more cumbersome (and expensive :() than I had hoped.
But we’ll get there.
In the meantime, I discovered these videos:
In the first post is discribed how to “teach in” the channels via openHAB. But I assume it’s easier using the PCT14 software (as shown in the first and second videos), and only then connecting everything to openHAB?
Or would that not work for some reason?
Is that because it’s an FT55? Because that’s the only device listed in the binding documentation as rockerSwitch: EnOcean - Bindings | openHAB.
I’ve got physical switches, which would be ‘read’ by a FTS14EM, which isn’t mentioned in the documents. But I see it mentioned in this dicussion here and there. So I assume it’s possible to ‘read’ them in openHAB…?
Hey,
sorry, missed your last post with the videos. Haven’t watched them yet, don’t have the time 
Yes, my wallswitches are FT55. It doesn’t matter if they are teached into anything else. You don’t even have to teach them into OH.
All you need to do is add a new EnOcean Thing - Rocker Switch Type and then type in the EnOcean ID which you find on the back of your switch.
Of course you need to have a working Bridge configured in OH. I.e. a Fam14 or USB300 stick. Still, I know nothing about the FTS14EM. I don’t know if this could work as a bridge.
Did you try this route?
It’s not the bridge, it’s the device that ‘reads’ the wired switches signals. The bridge would be FTS14KS, which should also work, as per community talks (Beginners guide for implementing Eltako FSR14, FSB14, FUD14 via FGW14 - #41 by ErikDB).
It’s only been an hour
You can setup everything with PCT14. I made an excel file for my setup where the addresses are calculated.
You can write the openhab IDs (gateway base id + address) into your enocean devices via PCT14 and then create the things in openhab with the associated IDs (Base id + address).
The teach in via Openhab is not necessary.
I use several FTS14EM with openhab. Not only for switches, for window and door contacts too.
This works without a problem because the EM just sends the messages into your bus like a normal wireless rocker switch would do it.