Firstly, the shortcode doesn't seem to have functionality to display content or excerpt, not a serious problem but i did have to a hack your code ;-)
(I wanted excerpts, no title followed by "read more" - if anyone wants this message me)
An elegance issue: my scroller is quite large, 350 pixels deep so about 20 lines. Now I can see why there is a gap before the beginning comes around again (the div has to leave the screen before being reset) but is there any way of wrapping it so it is seamless? I do realise this might be a complicated ask but "don't ask, don't get"
The only reason I ask is because I think your plug in is simple, elegant and easy to use and thus worth pursuing with.