microlaunch Usage Guide

Step 1: Compile the program

I'm assuming you are on a Linux system.

Create a directory at ~/.config/microlaunch. (mkdir ~/.config/microlaunch)
Copy config_examples/proton_example.toml to ~/.config/microlaunch as microlaunch.toml (cp config_examples/proton_example.toml ~/.config/microlaunch/microlaunch.toml).
Edit microlaunch.toml and make sure its paths point to the correct locations. Of note is game_path - it is used to check for integrity and is required by Square Enix to log in.
Ensure you have a working Proton installation (with the proton binary) in the folder pointed to by proton_root_path.
Double-check your work.

Run microlaunch --gui (or cargo r -p microlaunch -- --gui). The client should launch, and its graphical interface should appear.
Enter your Square Enix username, password and optionally one-time password. Make sure to select your correct platform and account type.
Optionally, check the "Save information" box and read the disclaimer.
Click "Log in".
It will take a bit - the launcher is not frozen. You will receive diagnostic info in the terminal, but this contains sensitive information such as login tokens, so do not share it!
Ensure everything is correct - do not share your Unique Patch ID, as this can be used to log in as you - and click "Launch game!"
Wait a bit - FINAL FANTASY XIV should start.

Once you have logged in at least once with "Save information" checked, the program will store your username and password in encrypted form at ~/.config/microlaunch/sensitive_data.enc.
To automatically log in, simply run microlaunch (or cargo r -p microlaunch --).
To get back to the GUI, run microlaunch --gui (or cargo r -p microlaunch -- --gui).
You will see a bunch of terminal output, and after a while, FINAL FANTASY XIV should start!