Button STOP and PLAY in slideshow and the speed of changing images

Hi,

I would appreciate if slideshow had button STOP and button PLAY -PAUSE. I miss it. It is a must for slideshow.

Then I would like to have an opportunity to change the speed with which the images change, not the time you can see one image, but the times it takes to change to another one. Like it is done now it is very fast = rought, the change of image should be more smooth.

Thank you for considering my suggestions
Lenka