First off, GREAT looking model! I love the weathering on the wheels and lower hull.
The pictures look out of focus to me. It sounds like you are doing everything correctly, but can the image stabilizer (IS) mode be turned off. I had the same problem with my Olympus C2100Uzi many years ago. I had the camera on a tripod and the IS was on. All the pictures came out fuzzy. Turned the IS off, and the pictures were sharper. The IS is trying to compensate for a movement that isn't there.
Also, what level of image quality is the camera set to? Economy, normal or fine? Try fine ans see what happens.
The DPReview list doesn't show Autofocus available. Is it available? Can the focus point or points be moved around? my Sony H50 can move it's focus point. If it can be moved around, try moving it to the extreme ends and the middles and see what happens.
I don't see grain in the images, just lack of sharp focus.
I hope this helps,