No can't remember! At the long end it shouldn't make any difference but at the wide end it might do.
Hang on, I'll check!
Any difference is really marginal. Providing the main subject is in the APS-C frame, taking it full frame would give a margin for cropping variation if indeed the FF image might be wholly acceptable. It's amazing such a lens with a long zoom range and to all intense and purposes be practically FF compatible yet still be really light. OK, it's not the same as using the DA* 300mm and DA* 200mm but certainly more portable. Worth a few more comparison experiments (but in the daylight!)

I can get the exif on Flikr now, but it isn't carrying through to this site.

I'm not completely sure what you're getting at but some zooms seem to appear as if they have shorter focal length at closer focussing distances than they do at infinity. Notably the Pentax 18-250 gets close to 200mm at close distances! Is this what you mean? The DA 200mm should be pretty accurately 200mm but the Sigma may well not be at close focus.

Really great set of photos, well done. Shame the exif is hidden.

The goose was taken at 105mm at f5.6, so depth of field is very limited with FF. The eyes are spot on which is what one normally aims for. I do not see a focus problem here that a bit more DOF wouldn't have helped.
The Flying Scotsman photo was taken at an ISO of 12800, which isn't ideal! It isn't a focus problem.
Also, maximum zoom isn't always ideal for best definition and both were taken at 105mm.

Has anyone worked put where on the K-1 body the potential scratch may be occurring as I cannot detect any evidence of this?

Sounds as if its OK with anything other than purely manual lenses, so at least it's still usable.

I see. I described what should happen, if it isn't then it sounds like there maybe an issue with the camera body. Has this issue just happened or is it a new to you camera?
What I suspect is wrong is the linkage known as the aperture simulator on the right hand side of the mount (as you're looking into it.) This is the linkage that was removed in later Pentax's, hence the term crippled mount. I wonder if that linkage lever has been removed or simply got bent out of position so the camera isn't able to read the aperture setting on the lens. If you have another Pentax film body perhaps compare those coupling levers. It might even be that the lever is working fine but something is broken where that data gets transferred to the electronics, possibly a dirty potentiometer.
If its a recent purchase consider returning it though you say the electronic metering is OK so you'll just be restricted to using that. I doubt it would be economic to get it repaired.

Ricoh's Pentax offerings seem to have improved on the out of camera jpegs (the K-1's jpegs are really good). The reason for the inbuilt raw converter isn't necessarily to process the images half way up a mountain (though one can if one wants) but to produce an improved image using the camera's inbuilt filters and adjustments, i.e. redevelop' the image in camera, possibly back at base camp when its too late to consider retaking the image!