Thanks to Lawrence Hortizuela on YouTube for the report on this issue. This affects most versions of the skin, including 1.7, on osu!stable client. osu!lazer is currently unaffected.
Solution
- Delete
hitcircleoverlay@2x.png from the skin folder.
- Rename
hitcircleoverlay-0@2x.png to hitcircleoverlay@2x.png.
- Reload the skin in osu! (Ctrl+Shift+Alt+S), and the issue should be resolved.
Why did this happen?
Usually the skin preview on osu!stable client shows the osu!standard set:

Since this skin is primarily an osu!mania set, I wanted to show the arrows instead:

A skin preview is generated from the following unanimated files:
hitcircleoverlay@2x.png
hit50@2x.png
hit100@2x.png
hit300@2x.png
In this skin, I set those files to each one of the osu!mania arrows. Now here's the interesting part of the trick - if an animated version of an element exists, it is used in gameplay instead of the unanimated version. An osu!standard player would have seen the following files instead (-0 means the first frame of an animation), which contain regular ol' osu!standard elements as you would expect:
hitcircleoverlay-0@2x.png
hit50-0@2x.png
hit100-0@2x.png
hit300-0@2x.png
Unfortunately this trick doesn't seem to work for the hitcircleoverlay any more. In a recent update to the osu!wiki, hitcircleoverlay is now shown as non-animatable. I don't know when this was changed in the osu!stable client, but I'm guessing fairly recently (as of July 2022).
Thanks to Lawrence Hortizuela on YouTube for the report on this issue. This affects most versions of the skin, including 1.7, on osu!stable client. osu!lazer is currently unaffected.
Solution
hitcircleoverlay@2x.pngfrom the skin folder.hitcircleoverlay-0@2x.pngtohitcircleoverlay@2x.png.Why did this happen?
Usually the skin preview on osu!stable client shows the osu!standard set:

Since this skin is primarily an osu!mania set, I wanted to show the arrows instead:

A skin preview is generated from the following unanimated files:
hitcircleoverlay@2x.pnghit50@2x.pnghit100@2x.pnghit300@2x.pngIn this skin, I set those files to each one of the osu!mania arrows. Now here's the interesting part of the trick - if an animated version of an element exists, it is used in gameplay instead of the unanimated version. An osu!standard player would have seen the following files instead (
-0means the first frame of an animation), which contain regular ol' osu!standard elements as you would expect:hitcircleoverlay-0@2x.pnghit50-0@2x.pnghit100-0@2x.pnghit300-0@2x.pngUnfortunately this trick doesn't seem to work for the
hitcircleoverlayany more. In a recent update to the osu!wiki,hitcircleoverlayis now shown as non-animatable. I don't know when this was changed in the osu!stable client, but I'm guessing fairly recently (as of July 2022).