Hmm... you seem to have everything you need for decent photos, especially the light tent. I just got one myself and this was the second shot I took in it...
This was taken with a Pro 1 but I spent four years with my G2 and you should be able to get the same results. Here are a few thoughts...
1. Considering your set-up, I would imagine you're using a tripod, yes? If not, you need to be.
2. Secondly, you'll be using ISO50, RAW, and macro mode (most likely). If you want the watch filling the frame, you'll need macro filters and a Lensmate adapter (although you don't mention closeness as being a problem). If you decide you want to go that way, however, let me know and I'll make some filter suggestions.
3. I don't know what to say about crisp focus... you take the photo when the green box appears. I assume you are then running your images through an image enhancement program. You need to sharpen anything you take, after the fact, rather than in-camera.
With those ramblings, I'll wait for a few more details from you.
Cheers,
Don