Try the following. First, put back %%ATTRIB__MOST_RECENT_DESCRIPTION%%.
To get the stamp that shows the who last edited the description, add the following line to your MRlocalDefs file (located in the FootPrints\cgi or FootPrintsServiceCore\cgi directory (it should be in a line by itself before the last line in the file, which typically is "1;":
$ALWAYS_SHOW_DESCRIPTION_STAMP_IN_EMAILS = 1;
See if that helps.