Same here.
On 10.5 Mojave.
The app worked fine for 2-3 days, then suddenly the wheel started spinning after opening a project: now it’s 2 days of colored wheel spinning for almost 10 seconds, then 2 seconds of activity then back to spinning again.I had to switch back to v10.
Unusable.
Toggling the preference for ruler/loop didn’t work for me.