It was there this morning and now it seems to have gone missing, all of the other templates are still in the list so I'm guessing it may have been deleted or hidden some how. Does anyone know how I can get it back please?
I can't see any reason for this to happen. Have you run FSupdate lately?
I suggest you run FSUpdate, and make sure it's setup to get the "FSL Script / Template Updates"... Then be sure you see it's applied in the FCM. The FSL Scripts:
Running Version: 7.0.289
that's as of this morning. I expect a FSL Script update sometime later today.
I hope that helps.