Error when manually adding user to project workspace

Question

I am currently using Project Server 2010.  I have a requirement for Business Users to have access to the project workspaces in Sharepoint but not be users of the PWA.  Similar to as it is outlined in this Microsoft Documentation (http://technet.microsoft.com/en-us/library/cc197668(v=office.14).aspx) 
There might be a circumstance where you want to grant people who are not members of the project access to the project workspace site. Anyone assigned to the Web Administrator group can create new users for a project workspace site. In addition to the
four groups that were mentioned earlier, there are four default SharePoint Server 2010 groups. They are as follows:
Full Control   Has all personal, site, and list permissions.
Design   Can edit lists, document libraries, and pages in the Web site.
Contribute   Can view pages and edit list items and documents.
Read   Can view pages, list items, and documents.
I have added the user to the Contributor group but when they try to contribute to the space, ie add documents or an issue/risk, they recieve an error, similar to as is documented in the following article (http://pwmather.wordpress.com/2011/07/11/manually-adding-users-to-project-workspace-project-site-in-projectserver-ps2010-ps2007-epm/) 
What has been identified in this article makes sense.  I am just wondering why Microsoft documentation states that it can be done.
Any thoughts?

Answer 1

Chris,
The Microsoft article says, users who are not part of the project. It does not say not part of project server. 
However, as far as I can remember, this scenario could work if the "Synchronization" is turned off between Project Server and Project Sites. I will run a test and confirm, later today.
Prasanna Adavi,PMP,MCTS,MCITP,MCT TWitter: @prasannaadavi Blog: http://www.prasannaadavi.com