I think in general we always put `ClassNames` in double back ticks.
Also, one of:

- "a very simple kind of slide; a SlideshowItem..." (slide is singlular with a semi colon)
- "a very simple kind of slide, a SlideshowItem, which contains an image and a label."

and

".. you want as an item for a ``Slideshow``, you can also mix .." (i.e. comma not full stop)