If you've tryed to install Business Analytics on Navision 4.0 SP1 with SQL Server 2005, I think you've found a serious problem: the system is unable to locate Analysis Services. 
Relax yourself... this is not an installation error but a Business Analytics problem and it's explained by Microsoft:
Customers that are running Microsoft Dynamics NAV on SQL Server 2000 and Business Analytics should reconsider moving to SQL Server 2005 until further notice.
The problem is that Business Analytics DTS packages etc. do not function on SQL 2005 components as these use the SQL 2000 object models. The Business Analytics DTS packages were developed as custom task that typically cannot be “upgraded” using the SQL tools.
In SQL 2000 these are made using VB6 and in SQL 2005 .net is the only valid solution.
Microsoft Business Solutions is working on solutions to this, and we expect that a solution will be available with the release of Corsica.
So, no Business Analytics on SQL Server 2005 until Navision 5.0. 