This is how I moved over my data from a Slashcode site to Drupal. It worked for me, might work for you, might not.
#Slash tables needed, dumpm'!
mysqldump --add-drop-table --opt -c story_topics_rendered journals journals_text users users_info comments comment_text stories story_text topics > SlashTables.sql
#need to change the name of the users and comments tables since they are the same in Drupal and Slash.
mysqldump -u -p db > db.sql
cp SlashTables.sql Good_Slash_Tables.sql
perl change.pl (this just changes the name of the users and comments tables)
mysql -u -p db_name < SlashTables.sql
##now, go to mysql and make the magic happen
##MOve over topics,Needs to go into term_data, term_hierarchy
gomysql
delete from term_data;
insert into term_data (tid,vid,name,description,weight) select tid,2,keyword,textname,0 from topics;
delete from term_hierarchy;
insert into term_hierarchy (tid,parent) select tid,0 from topics;
##Move over the Slash users into the Drupal users table.
##Move over all users who have, left a comment, written in their journal, logged into the site in the past 18 months(erso)
##maybe this needs to be done into 3 identical tables, then do a select out of them?
##Make Sure we get all the Journals Users (Slash users tables was renamed)
delete from users where uid > 2;