Redmine

hello everybody!

I want to migrate from Mantis. I found the destructive script but i need a non-destructive one (the Perl-Script doesn't work either). First question: why does the destructive script delete all data from the exsisting redmine-DB and why does it need a default redmine configuration? Why not inserting the issues, projects... and done. Why deleting the existing one? Are there problems with project, bug-id generation in the database? Can't ActiveRecord guarantee unique IDs?

I intend to change the script so it is non-destructive. And i only need to insert the issues with attachments and assigned_to-Users.
Projects, Users... are already in my Redmine-DB.

Thanks in advance!!

Daniel