Hi, really nice project.
Are there any possibilitys to create a 5x5 PCB with perforation, so that more jmodules fits on it? That would be great when ordering from dirtypcb's, because you have more pieces from just one Slice.
I have no skills with eagle or something, so i can't do it by myself :(.
Regards.
Oh, of course, i wrote Nano, my mistake 
I use Arduino PRO MINI's 3.3v for my Nodes.
I use this Module...
https://www.openhardware.io/view/386/Minimalist-RFM69CW-WeMos-D1-Mini-Shield
IRQ=DIO0= GPIO4=D2
CS=NSS=GPIO15=D8
I have researched and have found out that an arduino nano as a serial gateway also does not seem to work (same log as above).
I hope this helps you a bit.
Oh you mean which System uses the Data?
I use Fhem.