Hello! Sorry for the late reply - I've been working on rebuilding MasterPlan using a Linux virtual machine rather than my daily driver machine (Manjaro, which has a more up-to-day libc). Unfortunately, it hasn't been working out - I can get it to build, but elements of the GUI and assets aren't displaying. I believe it's due to using an older version of SDL2 on the Ubuntu VM I have...
In any case, thank you for letting me know, and thank you for building it from source - for now, that will be a workaround while I look into any solutions (either getting the VM up and running, or possibly building with a separate libc implementation? IDK for now, lol).