I've created a new database and am owner. The database test connection succeeds. I get this error after that part of the install:

The INSERT statement conflicted with the FOREIGN KEY constraint "FK_yaf_BBCode_Board". The conflict occurred in database "yafnew", table "dbo.yaf_Board", column 'BoardID'.
The statement has been terminated.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Data.SqlClient.SqlException: The INSERT statement conflicted with the FOREIGN KEY constraint "FK_yaf_BBCode_Board". The conflict occurred in database "yafnew", table "dbo.yaf_Board", column 'BoardID'.
The statement has been terminated.

Any ideas how to get past this?

I had this. Did a reinstall and DON'T CHECK "Upgrade BBCode Extensions...".

- Remove the SQL database and created a new empty one.
- Run "http://localhost/yetanotherforum.net/install"
- When you come to the page with 2 checkbox, when setting up the SQL database - don't check either one.
One checkbox says "Upgrade BBCode Extensions...". the other is about full text search.

If you do a search in the forum with "FOREIGN KEY constraint "FK_yaf_BBCode_Board" this happens a lot.
http://forum.yetanotherforum.net/yaf_postst15395_Error-Creating-Database-tables-during-install.aspx 

Unchecking "Upgrade BBCode Extensions..." worked. Thanks.