In the export help page, for parameters, it shows at the top of the table 'Parameters {%value="identifier" parameter="value"}'.  It looks to me as if this is the expected syntax for fields with valid parameters.  The parameters listed for "actors" are: template, maxvalues, params.
I'm trying to limit the number of actors exported to only the first five.  I tried this, but it still pulls all the actors.
{%value=actors maxvalues="5"}
Perhaps, I'm supposed to use a sub-template, but I can't figure out how to do those either.  Any clarification you can give would be appreciated.