Apparently locomotive #18 is being restored. Their mission is not very clear on their website. As I read various pages I gather they plan on restoring and running her on a short segment of the C&C. I'm assuming there is no track in place and they are going to have to relay track through the desert. Does anyone have a brief summary of what's happening?

There has been several posts on the Narrow Gauge Railroad Discussion Forum about this project.
See these threads:
SPNG #18 update (September 17, 2010)
SPNG #18 update (October 14, 2010)

In summary, it is a community effort with help from various knowledgeable people who know and work on steam locomotives. The initial plan is to restore the engine and have a short piece of track within the property used by the Eastern California Museum in Independence, California. And there will be steam ups for community events.

It is said that the work will be done to meet FRA requirements -- that is just in case it should get a chance to travel. Or a longer line gets built. Who knows what the future will bring.