The first thing I have to say is that I'm too lazy to write a full readme, so probably I will do that later. Sorry :))
I made a VM (Windows 7 32 bit) to build things like this, download it here (use at your own risk)
Running make u is a great start
Note: you cannot build full things for now, since the submodule mqtt in the module track and the module track_nvram contain undefined structs, and I cannot find them anywhere. The best thing you can do is fully remove the MQTT code from the code base, but that would be hard
Other modules should build, resulting in .lib files in build\GXQ03D_M2M_11C\gprs\MT6261o\lib with debug info, helpful for using with BinDiff when RE firmwares.
If you have any questions, please open an issue. Thanks!