You means vars_wordlets_mods.cgi. I did installed
but I find that in "last user name to post in forum" mod v2.02 get work. There is some different in ubb_forum.cgi, find $last_hyphen_date = $last_post[3]; in v2.02 and find it in ubb6.05 but in last reply mod 3.0 find $last_hyphen_date = $this_topic_data[12]; . This doesn't exist in
the ubb6.05. I guess mod v3.0 only good for 6.1.x.