Error retrieving the data serious error
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ' FROM j17_users u LEFT JOIN j17_comprofiler c on (u.id=c.user_id)' at line 1 SQL=SELECT u.id,, FROM j17_users u LEFT JOIN j17_comprofiler c on (u.id=c.user_id)

Once I save the configuration I get a 500 error.
The website encountered an error while retrieving www.bpm.com/administrator/index.php?option=com_cbjuice2&task=save&view=default. It may be down for maintenance or configured incorrectly.

I just migrated my site to a new host. What could I have missed?

Immediate suggestion is to check the consistency of your database using various tests such as the Tools in CB. Is there a possibility that your prefix got changed during your migration?

Looking at the code, it would appear that for some reason field names are not being picked up in the code at line 87 of save.php:

$full_field_names=$_CB_database->getTableFields(array('#__users','#__comprofiler'),TRUE);

The only other way it could happen is if you entered all the users and comprofiler fields into the "Fields excluded from Save" box.

jciconsult wrote: Immediate suggestion is to check the consistency of your database using various tests such as the Tools in CB. Is there a possibility that your prefix got changed during your migration?

Nothing wrong in the consistency checks...

Will this work with "mysqli"

It'll work with either Mysql or Mysqli.
Try turning on error reporting and see if you get any error messages.