MTB-GOA version 18

The first release in the new year brings a few requested corrections and more F->P annotations. As to the latter, it's at the moment a bit fuzzy how I will proceed with them. There seem to be no errors---at least I hope I would hear of them---but still, I will seek some feedback before I continue with F->P. Due to other work, this may well be the last release before the major one in July. Until then!