My game has a lot of items for each character. Certain shirts, pants, earrings, etc. Every couple of weeks, my artist will add a few new layers to the PSD or fix a few old layers, and it's my job to take the new PSD and incorporate those changes into spine.

I've been doing this by following some advice that Erika gave me: I use the script in photoshop, then import the json as a new skeleton. From there, I think I'm supposed to drag over the new slots into the old skeleton and delete the new skeleton, but I'm stuck on one part:

When I created the original skeleton, I dragged all its pieces so the character's feet are at coordinate (0,0), but when I import the new skeleton, all the pieces appear at the lower right quadrant. If I just leave it this way, dragging the new slots into the old skeleton leaves them in the lower left quadrant, but that's no good, because the old skeleton's body is above (0,0).

To fix this, I've been dragging the new skeleton over the old skeleton, then I drag the slots over. But dragging over the new skeleton with my mouse is highly inaccurate and I'm always off by a few pixels. As a result, I spend 30+ minutes adjusting the pixels of these attachments to get them just right (even though they're already right in the PSD).

Now to my actual question: Is there a better workflow than this, or is there a way to make the two skeletons overlap perfectly?

Nate wrote

You can set the ruler origin in Photoshop and it will correspond to 0,0 world coordinates in Spine. We've just created a video for explaining this which will likely be ready to release tomorrow!

We also have short term plans to augment Import Data to bring the data into an existing skeleton. You can track progress here:
Import Data into existing skeleton · #465 · EsotericSoftware/spine-editor

Oh perfect! This is a lot easier than I anticipated. Thanks a lot.

OK, it seems to me that the origin can't be saved in a file and every time you open it, it resets to the upper left hand corner. I can use grid lines to help me position the origin every time I open the file, but that won't be perfect, so each time I export into spine, the new skeleton will be off by a pixel or two. Is there a more precise way to do this? I'm also concerned that the grid lines will interfere with my artist, so he'd want to remove them, and that will make it even more likely that I'll be off by some pixels.

Yeah, I watched your video on how to do this and that's what I'm doing, too. But it seems very easy to get the origin off by a pixel each time since you have to use your mouse. Is there a way in photoshop to set the origin by typing it in or something? That way I can't be off.

Perfect! Thank you!