...perform a "slow motion?" The clip should get bigger and all rest of the clips should all move down to the right.
It doesn't work that way... changing the speed of a clip
in the Timeline will not perform an automatic ripple edit.
You will need to have enough gap to accommodate the new duration.
You can file a feature request here:
When changing speed the adjacent clip does not automatically move to the right.
You need to make room for the clip first.
If you want the slomo to last for 8 second, you need to make a gap first that is 8 seconds long.
I come from Final Cut 7 and when I do a slo mo it just moves everything down to the right on the timeline. That is what I am used to.
I just did it in Premiere and checked the Ripple Edit check box in the Speed Duration Dialog box and then add slo motion, , and it did move everything to the right, but I had to render all of the stuff that needs rendering all over again. Don't want to do that everyime I change speed on a clip.