Just an update on this: I have added a new customization UI to the website so that it is easier to customize mastercomfig. This will be a replacement for the app moving forward. Check it out! https://mastercomfig.com/download
These also include some backend changes which allow more of the config to be generated dynamically, opening up the door for the config file to come in several different varieties.
In the future, I plan to add offline support to the download page, so that it can be used as a full replacement to the app. Then, I will add more advanced scripting features like binds, per console variable documentation and toggles, and more. After that, I may bring the download page out of the browser into a local app so that it can also help with putting the files where it needs to, like the old app.
We're also still working on the video, but given how things are changing, we are kind of holding off on most of it for now.