In order to have Drupal support for imported users, it’s necessary to amend the existing Drupal importers so they will fill the import_pass field. The base importer has support for this so all you need to do is feed the applicable database field into the structure you feed to create_users with the key password. For example, the VBulletin importer does that here.
For the Drupal importers, that’s here and here.
Step 2 is something that is not and never will be required or necessary. Where did you get that from?
You should enable the plugin AFTER the import and leave it disabled during the import.
So the correct steps are:
- import users
- install and enable the plugin