LastNonEmpty + Time PrevMember don't aggregate correctly

I'm using the Account Intelligence and when I have a balance account modified with a mdx script in cube calculation using the Time prevmember it don't aggregates correctly. I think that it's a solver order problem.

I have a account dimension like that:

Balance (balance account)

Asset (balance account)

Computers (balance account)

Result (flow account)

Computers Investments (flow account)

In the cube calculation I have these formula:

Computers = (Computers, Time.Currentmember.Prevmember) + Computer Investments;

When I query these data I receive these:

2007 Jan Fev Mar

Balance 0 100 50 0

Asset 0 100 50 0

Computers 150 100 150 150

Result 150 100 50 0

Computers Investments 150 100 50 0

It's not aggregatin the (Computers, Time.Currentmember.Prevmember) in account hierarchy, any Idea why is that?

I'm using SQL Server 2005 Enterprise SP1.

I was using the follow Time Hierarchy:

Year