The 8266 controller is an older design and has not been updated for a few years now. I recommend not using that if you are planning to build a new setup.
As regards to the clearance violations, I’m not sure, KiCAD was used to generate the designs, and it passes the internal checks in that tool. The circuits have been built using the Gerbers supplied without issue.
Can I ask why you need to add new text to the silkscreen?