I purchased a few puck.js (all of them are hardware version 2.1a) and all of them seem to have a problem with the "newer" CR2032 battery, that are a little bit thicker, due to the surface on the back.
I had to resolder the battery holder, and put a little bit more solder on the surface but obviously that is not the best solution (and I am not nearly as good in soldering as the machines in the factory are).
I definitly affects other products as well (see https://www.youtube.com/watch?v=zz1POx0fw2w
), and I ask myself, if there is a better way to make the battery holder more robust. Maybe it is possible to change the holder with a other version like https://cdn-reichelt.de/bilder/web/artikel_ws/D600/BH1060.jpg ?
Hope to hear from you guys, if you have similiar problems.
BTW: Thank you @Gordon for all the great work you are doing. If you will ever be in Berlin/Germany, you will be my guest in every possible way :P
All the best,