AVL Roadrunners are controllers for multiple slide projector shows. I have
only seen standalone ones like the commodore type you mentioned. Since this one
had video it is probably for adding or switching video in a multimedia show.
That thing is probably Z80 or 8 bit controlled, maybe STD bus. All of the
pieces go together. This must have been a high end system, probably worth saving.
IIRC AVL stands for Audio Video Laboratories.