Overlay animation duration and looping

Overlay animation minimum duration is 5s which is too long for some some animated GIFs last less than 5s and are looping. It would be great to be able to set a duration from 1s and being able to adjust it precisely (ie 1.25s) Adding an option to disable GIF looping would be apprediated too. It would be great if we could also adjust the duration of the transitions.