Super noob question (sorry)

All,
Sorry for the super n00b question. I’ve never done any real skinning, just made some tweaks to one that I’ve used.
I recently updated to Kodi 17 RC2 and, as expected, the skin isn’t compatible. Kodi gave me a pop-up that said as much, and disabled it.

So, my questions are:
1) What do I need to do to enable it again, so I can make modifications so that I can resolve whatever is wrong with it.
2) What can I look at to determine the incompatibility, and fix it? I reviewed the changes thread, but it doesn’t seem obvious to me on where to begin.

Thanks!