Animation does not Scrub I'm using mp4 video projected onto a 2d plane in the 3d viewer, but cant get them to animate or scrub through timeline in texture or material mode unless I open up an extra window with cycles render on. Is there a way to simply allow it to animate without having to open up an extra render preview window?

PS: Thanks for the support on my last questions. you Blender Gurus are the best!
If you use video as reference, best way to do this - using image empty. 

Image empty always shows current frame; over methods, that i'm tried gives +-1 frame offset. To add image empty press Shift+A -> Empty -> Image