The GenMerge Trial is a full functioning copy of GenMerge which you may use for 10 days.  The only difference between the trial version and the licensed copy is the output GEDCOM file.  The output of the trial version contains only the GEDCOM data required for record linking and none of the other modifying information.  So the names and dates will appear in the output but not the sources for those names and dates or any notes, media, etc.  Since all merging takes place in memory, the 64-bit version allows more individuals to be processed.