Morning barcarat,
I do like the website for your housing, especially the way they highlight the features. I also see that they support a number of Pentax models - even the K7...
The last time I went diving was 30 years ago and it was with an old clunker of a film body that the marine biologists were using for a sub-tidal survey.
But the reason for the post is, I did not see specifically how the shutter release was triggered. It appears that on the Diveross model its a physical assembly depressing the shutter (hence their shutter depression adjustment). On the SPL site it looks like they might use the external shutter release.
I have found that using the wired external shutter release, you can trigger the shutter even if the camera body is off. I do this all the time when using my tripod. I stumbled on this by accident and have found it very convenient not having to turn the body on first, especially across a long series of images.