This is pointless.
The SGL files are encrypted binary files which look like random numbers.
You could decrypt the sgl files into the machine code file (or just build the machine code from the source code), but this would still look mostly like random numbers apart from the on screen texts
If you wanted to decompile the machine code, you could use a tool like Ghidra or Radare2, but the resultant assembler and C code would be very difficult to read, because most of the files are compiled with compiler optimisation enabled, which effectively rewrites the C code to make it go faster but makes it very hard to understand.
Why don't you just look at the source code on Github ??
https://github.com/rogerclarkmelbourne/ ... are/source