Did you post about this in another thread where MiddleValues was being used to extract the value for $$CurrField from a list of such names?
The problem in that thread--and might be the problem here, is that middlevalues tacks an extra return on the end of the value extracted and this won't prevent evaluate from correctly evaluating but will case set field by name to fail.
I suggested in that other thread that getValue be used instead of MiddleValues as that way you can extract the fieldname reference without getting that extra return.
I may be completely off base as to that other thread but the presence of a trailing space or return would produce a situation where evaluate works, but set field by name does not.
I did post in another thread, but it is a few days old without a response as of this morning. Maybe I'm not seeing your response somehow. Yes, it is using MiddleValues, so I will check into that and see if that is the problem. Thanks, again.