I have the following UDC:
MC.Utils.FindAndReplace REPLACEALL MODE="Many" FIND="fff\nddd" REPLACEWITH="zzz\naaa" FILE="d:\\temp\\1.txt" TARGET="*_new.*" SILENT OVERWRITE
It works if target file doesn't exist and doesn't work otherwise
UPD. It seems that TARGET param doesn't support direct file names. I.e. if TARGET="d:\\temp\\1_new.txt" it doesn't work. Mask works OK.