The parameter seams to be saving fine in my tests. Are you saying it isn't saving or your changes are doing nothing on frontend? Please note each tab can display each gallery individually. Specifically if you edit the File tab and adjust the Photo parameters it does nothing to the Photo tab. Ensure you're on the correct gallery and adjusting the correct galleries parameters.

Was able to confirm. It's checking for a plugin param when that's a tab param. Fixing for 1.0.3. Please note the date format at the top of the folder is configured under Folder Items > Display. The items themselves are configured under Items > Display and folders on profile are configured under Folders > Display. So 3 parameters due to 3 completely different style structures as they each have different space limitations.

forge.joomlapolis.com/issues/5134

1.0.3 will be released today. Shortly after fixing this actually.

No, you don't need to change it for every sub-tab of every gallery tab. Only what's displayed. So by default Photos > Photos, Videos > Videos, etc.. you need to adjust 4x3 = 12. You also only need to do this once. The only reason to do this 39 times is if you are displaying all 4 galleries on all 4 times at the same time.

Each tab can display every gallery. The idea behind this is the tab code is written once and reused. All 4 gallery tabs have the exact same code that's written only once and has to be maintained only once. Yes I can make this less confusing but less flexible by forcing each tab to function only as 1 gallery, but then what if someone wants all the galleries under a single tab? You can have 2 galleries under 1 tab and 2 under another tab or all 4 under 1 tab; it's entirely up to you.