exTimeline is a small, free Extension to help you create timelines in the same sense as GameMaker Studio already provides but with extra features:
End User Licence Agreement (EULA).
! A few extra arguments have been added to functions and order has been swapped around, please check if this breaks your project first
Fixed frames not executing when using a speed that was not strictly a value of 1 and some other cases
Correctly get the current (floored) position now while in a script
Added syncDelta argument that allows the timeline to autosync to delta_time, default is false
Added argument support for onComplete argument, supply them as an array, up to 15 arguments allowed