Migrating from FileNet P8 4.0 to Alfresco (reading MSAR surface.dat files ?)

I'm currently trying to migrate one of my customer's ECM system from FileNet to Alfresco.

Since they are using Filenet Image Services 4.0 SP4, I cannot take advantage of CMIS (only available from 4.5.x).

According to this blog in more or less similar conditions :

• http://blog.tsgrp.com/2010/08/24/filenet-migration-findings/
• http://blog.tsgrp.com/2010/02/09/migrating-from-filenet-to-documentum-could-openmigrate-possibly-do-that/

The best practice seems to be reading the database to find all documents (data + link to image) :

1. Does anyone know how to achieve that (retrieving the document from system tools) ?
2. Does anyone know how to read directly MSAR surface (.dat) files that already contains all information ?

I think the best practice is to use standard FileNet Image Services Resource Adapter (ISRA) if you can.

Product Documentation for FileNet Image Services Resource Adapter