Yes I think it’s possible to show the video but not slides so easily. Here’s a suggestion or two:
If you have two monitor outputs on your graphics card (or laptop) then I think you could set one of the outputs to full screen video while the other would be showing the Cb project window (i.e. the usual desktop display). IIRC full screen video is achieved simply by double clicking the video picture in Cb and it becomes full screen - at least that’s what I think my system does (but I rarely use it in full screen).
So, this would allow you to show a video and play music. But Cb can’t do slide-shows, and it can only show 1 single video per project (Nuendo shows more than one, maybe Cb6 does now, need to check!). So, you’d have to cut everything to a single video and import into Cubase. That severly reduces your control of the slides or video start/stop during the show…
Also, bear in mind that Cb isn’t designed to be a video presentation tool so you may find it’s not always smoothly shown. Also you may have some issues with resolution of the video, not sure about this tho. Suck it and see I say, but test it fully before using it for a show. And let us all know how it goes