It seems there are some variables (but those might belong to cpp libraries then they could not be used in scripts), but no more functions:
__cur_mp
__SERVER__
__cur_sp
__PLAN
__BRIEFING
__STATISTICS
__DEBRIEFING
__OBJECTIVES
__waituntil = _time+(%s)
__emissive
__specular
__diffuse
__ambient
(material properties of textures)
__EVAL
__EXEC
I haven't found anything exciting. You can have a look yourself, open the Flashpoint.exe with a notepad (or hexeditor) and have a look at the stringtables (close to the end of the file). Every string (~"word") that is used by the engine (and is not defined outside - and the script commands are not afaik) is listed there, but all the strings of included libraries too (math commands, error messages, directx and direct draw messages and so on...).
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