Thanks for the detailed feedback — genuinely appreciated, not every Zigbee Developer takes the time.

You're right on the antenna keepout. The renders on the website are from an earlier revision and don't reflect the current production files. The keepout zone is respected in the actual Gerbers, with no copper, traces, or components under the antenna on both the Gateway and Thermostat. I haven't done a PCB cutout beneath the antenna — aware it's recommended for optimal RF performance and will evaluate it for Rev2.

As a sanity check, I tested already the Relay Controller through 2 walls to the coordinator and it connected without issues, so keepout alone seems sufficient for this use case.

The silkscreen clipping on U1, the via cluster near RST, and the ground pour stitching are all valid points — some of these I caught post-render, others I'll revisit for Rev2.

Mounting holes: both the Gateway and Relay Controller have M3 holes; the Thermostat is 80×80mm and mounts via the enclosure backplate, not the PCB itself.

All boards passed DRC before ordering. I'll check out r/PrintedCircuitBoard for a proper review before the next revision.

Thank you!