Problems upgrading from B2

Hi all,
when I try to run the import-b2.php get the following errors during Step 2, and nothing gets imported. As the readme or the tool don’t say anything about how to solve errors, I hope someone on here can help me out. The is the output I get during step 2:
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Step 2
First we’re going to add excerpt, post, and password functionality…
Database error: [Duplicate column name ‘post_excerpt’]
ALTER TABLE wp_posts ADD COLUMN post_excerpt text NOT NULL;
Database error: [Duplicate column name ‘post_status’]
ALTER TABLE wp_posts ADD post_status ENUM(‘publish’,’draft’,’private’) NOT NULL, ADD comment_status ENUM(‘open’,’closed’) NOT NULL, ADD ping_status ENUM(‘open’,’closed’) NOT NULL, ADD post_password varchar(20) NOT NULL;
That went well! Now let’s clean up the b2 database structure a bit…
Database error: [Can’t DROP ‘ID’. Check that column/key exists]
ALTER TABLE wp_posts DROP INDEX ID
One down, two to go…
Database error: [Table ‘boneless_nl_-_wpress.wp_settings’ doesn’t exist]
ALTER TABLE wp_settings DROP INDEX ID
So far so good.
Database error: [Can’t DROP ‘post_karma’. Check that column/key exists]
ALTER TABLE wp_posts DROP post_karma
Almost there…
Database error: [Can’t DROP ‘ID’. Check that column/key exists]
ALTER TABLE wp_users DROP INDEX ID
Welcome to the family. Have fun!
———-
Ofcourse b2 and wordpress are installed in different directories (boneless.nl/blog = b2, boneless.nl/aa = wordpress) and they use different databases.
How can I get a succesful b2-import?
Thnx for helping,
Boneless