I tested the assemblies I keep for further development and sent out the others to some friends for analysis. It seems there is no hardware bug so far.

Now is the time to prepare how to produce a larger batch. Seems the advertised prices for assembly on pcbway are somewhat subject to arbitrary change. The SMT cost (mounting only, components cost extra) was estimated at 230 US$ at pcbway.com. After review the cost was 370$ (increase of 70%) due to the fact that 4 components have >= 16 pins, one of the components in question is the rediculously expensive 40 pin header that can be connected from both sides...

The other question that came up when putting it on tindie was shipping...  Apparently Corona Virus affects the postal service. DHL now does no longer ship “Päckchen XS” i.e. small packages to the US. This drives shipping costs beyond reasonable…

https://www.dhl.de/de/privatkunden/kampagnenseiten/coronavirus.html#usa