If while using the migration tool, it looks to stop at Building File Mapping Table, this means that your Filemap.dat and Filemap.ps are either too big or they are corrupt. What you can do is copy those two files (located in the SW folder of the RIP) from the new rip, move move them to the old RIP. Make a backup of those two files from the old RIP before copying from the new RIP. This will allow the migration to take place without any issues.