One way to provide the scrolling credits:
Not the simplest:
Create the credits in PhotoShop as one “tall” file, import into your AE project and
edit the Y position over time – starting with the PS file off of the bottom of the screen.
Not elegant but it would work.
Another suggestion is along the same line – a bit more elegant.
Create a new layer in AE for each element.
Position each layer off screen bottom, set a keyframe, move the layer off screen top set another keyframe.
Adjusting the position of the keyframe in the timeline to control the speed at which the layer scrolls.
Do this for each layer of the credits.
Also try adjusting the opacity to fade in as the credit/text/image gets to the middle of the screen and
fade out as it rolls off screen top.
There are many other ways to get the same effect (rolling credits) but these should get you started.
If you would like some help, I’d be glad to assist – gratis.
John