Saving Status UI to let users know when a score is saving

Your idea

Provide an indicator that lets users know when a score is edited in if saving is in progress.

Currently, the file title shows a * when the score has been edited and not yet saved. This could be more aesthetically pleasing, but, more importantly, this indicator could also tell a user if a score is saving.

Concept Art (edited state is the left image, saving state is the right image

In this concept, the saving indicator is limited to the title tab.

Alternatively, there could be an entire saving progress window that will prevent users from accidentally (or not so accidentally) interacting with the score while it's saving.
Concept Art (score editing UI is greyed out, while a saving progress window displays a waiting message, a progress bar, and the percentage)

That sheen seen in the concept should be animated to let the user know that the app is working and not frozen.

Problem to be solved

Saving large files can take some time and the current UI for indicating the saving state is limited to an asterisk. Sometimes, the app is frozen and I don't realize unless I click anywhere on the app, and then is whitens and other Windows indicators show it's frozen or about to crash.
Implementing a similar UI might provide users peace of mind, knowing that their score is indeed being saved if it happens to take longer.