Customization guide

[gitgitwhat]

• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the issue tracker for a feature request that matches the one I want to file, without success.

Is your feature request related to a problem? Please describe.
Not a direct problem per-se yet but I'm just starting to modify the code base so I'm sure there will be issues. I need to remove all external connections and references (will be running on a closed network) and have the drawings saved to a database.

Describe the solution you'd like
The README states:

The default libraries, the menus, the toolbar, the default colours, the storage location, these can all be changed.

However, I can't seem to find where it is explained how to change these. Is there a guide that I'm missing or do I just have to figure it out?