How to build and upload custom firmware from source code

I'm trying to build and upload firmware to my device from the source code here:

https://github.com/interactionresearchst...

I'm running into a problem where the device reboots when I try to connect it to WiFi. I've written out the full issue here and intend to add a section to the readme on how to modify the firmware and upload a custom build. Is there any further documentation available on how to do this that might help resolve the issue, and if not, could you help me work through the issue below please?

https://github.com/interactionresearchst...

Thanks,

Adrian