The Documentation for Tiny Rocket seems to be the documentation (at least in part) for PixelPioneer (for example the slide demo example) and there does not appear to be a way to change the slide height and width. Is an update planned or am I possibly confused?
Uuups, yes...you are right.
I correct this. But as far as I can see it it was the only fragment from the PixelPioneer doc.
But you don´t have to setup the hight and width. The width is taken from the templates width and the hight is calculated automatically.
If you want to use a full size image which resizes depending on the templates body width (...which depends a bit on the browser window width....) give the image the width value "100%":
<img src="sample/url/to/image.jpg" width="100%" />