Are there mission editing reference manuals available for the experienced mission maker?

Sure. BIS has produced an official OFP Scripting Command Reference Manual, up to date for OFP: Resistance. You can view it online (an XML supporting browser is required) or download a copy, both from BIS' OFP editing page.

For older versions of OFP, a similar guide is available from Merciless Creations in PDF format, at FilePlanet and Merciless Creations made available a 300+ pages long OFP Mission Editor Reference Manual, in PDF format, also at FilePlanet.