Like so often, I struggle with something for days, and all it takes to find the solution is to post publicly to find the solution 10 second latter! God’s way of keeping keeping us humble I guess.
Solution:
Simply change the “Time” setting of offending elements from “all” to a time equip or longer than the slide length!
So a note to the developers: it appears that (attest in Safari) that “Write “all” to set the entire time” should actually read: “…entire time less one frame.” 🙂 Thanks for your hard work on this slider!