Thanks for your looking at this.
I’ll start by answering your last question. After shutting down OpenHAB, then unplugging the device, pairing with new devices, re-plugging the usb device and starting OH again, it sometimes does not recover the existing USB setting for some reason. Now, I am not 100% sure why that is, but I found some rogue process that could have been stepping on the feet of OH when accessing the device (/dev/ttyACM0). Given that I’ve gotten rid of that process and that it is not something I can re-produce, unless you have some idea of something to do before the next time I re-plug in the device, trying to discuss that part is in my view futile that I discuss further that aspect.
However, given that the stick did not appear anymore, I tried to get it back. And there, I may have made a mistake, i.e. create a new stick rather than go back to the original thing and make it bind to the stick afresh…
In any case, I started the PaperUI interface to add a stick and it does pick a random ID. In fact, it has to be random, since it is done before even telling it which port to use. I tried to change that ID to the old one, but that didn’t work.
Eventually I cleared up everything, backed up my files, uninstalled OH, upgraded linux, re-installed OH, started afresh with the things, and eventually could add back the items, using my original .items file after substituting the new ID for every occurrence of the old one.
As for my id of a symbolic name/variable, I was not assuming it was currently allowed in the framework, but it might be something worth considering in adding to the framework. Such a feature could have other broader beneficial impacts.