>
> System > Trigger once > starburst > Set rotate speed to 45 degrees per second.
> starburst > enable effect "Rotate"
Maybe you need "something" trigger before "system > trigger once" ?
I dont know if this .c3p that I made for other post could show a little bit that related to your condition
https://www.dropbox.com/s/mpbz9r9kcxbaz4z/testRollPlatformer.c3p
From unrelated post : construct.net/en/forum/construct-3/how-do-i-8/how-do-i-make-a-ball-roll-down-139612
I do have something that triggers the event...
System > Score = 5
-- System > Trigger once > starburst > Set Rotate speed to 45 degrees per second.
--------------------------- starburst > enable effect "Rotate"
There's another event in the full event that runs when it should, so the full even t looks like this:
System > Score = 5
-- System > Trigger once > System > Create object StarParticles on Layer 10 at (240, 1087)
--------------------------- starburst > Set Rotate speed to 45 degrees per second
--------------------------- starburst > enable effect "Rotate"
The event to create the StarParticles runs fine - but the rotate doesn't run.
The file you attached (testRollPlatformer.c3p) doesn't open in my version of C3 - error message: Failed to open project. Check it is a valid Construct 3 single-file (.c3p) project.