For the mouse, you may only adjust the starting position on the first slide where it appears. Every slide after that uses the stop position of the slide before as the start position for that slide. If you need to adjust it, duplicate the slide and remove all objects except the mouse. Change the mouse to the new desired starting point and adjust the mouse and the slide so the play time is super brief. Perhaps .1 seconds.
As for the tabbing, you may need to insert a Click Box that doesn't do anything if it is clicked. This would then receive the tab focus and keep it from the playback controls. Or, you could visit fellow Adobe Community Expert Paul Dewhurst's site linked below and download a gizmo that will remove the highlight.
If you like what Paul has to offer, drop some change in his tip jar and he will open the door to all his magickal goodies!