Currently I can’t unfortunately, as a friend of mine has lend me the device for testing, before I buy my own one (don’t wanna spend €400 in case it’s not working). So at the moment it’s not connected any more.
Nevertheless I’ve double and tripple checked the wiring. During setup the initial one proposed by the app didn’t work, but the alternative one was recognized correctly, which is:
existing wire of L2 -> clamp
red + yellow -> clamp
orange + green -> L2
black -> L1 (together with existing wire)
So like you did in your screenshot in post #1, just with exchanged L1/L2. I can definitely guarantee that the wiring was done 100% as stated in the app. Further, every setup step (except the last one) was working. So even ringing at the front door and manually open by button press in the mobile app. As the intercom needs preactivation that implies, that also the ring signal must have been detected correctly as well as the button press of the opener on the intercom itself. Otherwise, the step prior to the last one (automatic opening on ring) wouldn’t have worked. The only thing I haven’t tested yet is to increase the delay for “open on ring”.
Did you get your opener running in the meanwhile? If there’s someone out there, who could get the Urmet 1740/954 working and can confirm that, I’d even be willing to by my own set, of course.