Hello ! My game is using a lot of timelines and is taking ages to compile. Is it possible to use GMLive on timelines so that I can change one, have it reloaded ingame live, and keep changing it or another timeline ?

:D

You cannot use GMLive for timelines in an intuitive way because every timeline "moment" is a "script", therefore you cannot live-code adding moments to timeline.

I would suggest custom timelines, especially in light of timelines likely being deprecated in favor of sequences in a few months.

Thank you for your answer, I'm still on old GMS1.4 but migration is plan of my roadmap. I'll come back to GMLive after migration then.