I prefer tiled background, here is a demo:
I don't know your game, so not sure what will be the right way to pick Minerals instance. If only one mine can be built at a time and you only need one progress bar, you can pick by UID or custom ID variable.
If you need a separate progress bar for multiple mines, you can link them with hierarchy, or put in a container, or use MineUID instance variable on the bar object.
I'm glad you posted that demo as
it's the one I've gone through it's the one I thought I had reviewed.
The problem I had was that there could be multiple mines/structures that could be built, eventually with different build times. So I wasn't sure how to get the progress bar (or it's equivalent) to show for different builds.
Testing it now to see if I can figure out how to associate it to different builds.