ModMaker alone is probably about 40,000 lines of code. I built extra tools into mod manager users can't access that I could copy/paste bioware's coalesced XML snippets and it'd auto generate it stats code, since a ton of stuff is repetative (like all weapons for example). There's essentially 5 parts to every different part of modmaker and then one for every update:
- SQL code to add to the genesis entry (bioware values)
- Fork Code
- Page Code (PHP interface code/Javascript validation code)
- Saving Code (PHP backend)
- Publishing code
Then I'd bundle up all the genesis mod additions and apply the defaults to every mod. Typically if I did each step individually for say, a power, it'd take about 3-4 hours each once I perfected the process. The main server mainly does matchmaking and telemetry data, the rest is P2P.
Additionally I have to capture images for just about everything, which for powers took signficant amounts of time (typically 1-2 hours for each power. Turiathar was a big help)
ModManager's code for ModMaker is probably about 3000 lines, the compiler is about 2000. The compiler is really straightforward but it has a ton of checks to fix bioware's problems.
As far as I am aware all communciations between blaze (the backend server) and your client ME3 are over SSL. A file called ME3BINI.bin is stored on the server and downloaded into memory every game startup that supercede *some changes*. Some changes are overridden but due to the way things are scanned for when you modify it it can't figure out how to replace it.