I have a saved search with a formula in the criteria. The search runs perfectly in the UI (returns 36 results). I'm trying to do a map reduce using the data from this saved search and I'm getting this error:

{
  "type": "error.SuiteScriptError",
  "name": "FORMULA_ERROR",
  "message": "Your formula has an error in it. It could resolve to the wrong datatype, use an unknown function, or have a syntax error. Please go back, correct the formula, and re-submit."
}