Windows 2003 x32 CA to Windows 2008 x64 CA migration

In the following period I have to migrate the AD over to 2008 schema level.

I currently have a x64 Windows 2008 R2 domain controller and one x32 Windows Server 2003 domain controller. The x32 server is a old machine which doesn't even support the upgrade to 2008. I have began my transition plan and installed 2 servers (one with 2008 R2 x64 and one with x64 2003). No problem with transferring the roles, but I can't seem to be able to transfer the Certificate Authority (CA) over to a x64 machine.

1. Scope

   1.1. Upgrade the AD schema to 2008.

2. Restrictions

   2.1. I can't use the old root server as it doesn't support Windows Server 2008.

   2.2. I have to get to x64 as Windows Server 2008 R2 doesn't support x32.

   2.3. I have to move the CA because I have to demote the server.

3. What I've done so far for the CA move

   3.1. Installed a x64 2008 R2, tried to make the restore of the CA there -not working. It should work, but it doesn't according to this TechNet.Error message "Restore of an incremental image cannot be performed before you perform restore from a full image. The directory name is invalid. 0x8007010b (WIN32/HTTP:267) "

   3.2. Installed a x64 2003, tried to make the restore of the CA not working because the database is in a different format.

Any ideas would be greatly appreciated, as a last resort I can keep the CA there, but to keep a server only for a CA role seems pointless.

What i'm trying to do now :

1. Created Image with disk2vhd of the old physical server.

2. Got the image running in a isolated VM on Hyper-V (without networking )

3. Extended disk in order to prepare it for an in-place upgrade to windows 2008 x86(since the physical drive had only 14 GB on C: - done that with GParted after I've deleted the D: partition to make room because I have a basic disk - not a dynamic one)
4. Powershell needs to be uninstalled if you go on that path , after some searching I couldn't find that KB with powershell , so I've deleted C:\windows\system32\powershell .
5. Ran adprep/ forestprep ,adprep/ domainprep,adprep/ rodcprep - I want to get a RODC in place after the upgrade , that step failed , but I supose it should have because I only have the Schema Master role there , the rest are migrated to another DC and since the DC doesn't have network connection it can't see it / upgrade it .
6. Result BSOD without a error code , going to try that again .
7. Update 1 : Restarted the server a couple of time before the upgrade and escaped the BSOD , but when I try to boot it just gives me the error about "vmbus.sys" missing which I discovered it's part of Hyper-V integration tools (thanks MS!) . Going to take the backup and uninstall Integration tools 1st then attempt the upgrade (Uninstall didn't work so I just took another backup).
8. Update 2 : Managed to upgrade to windows 2008 (not R2) x86 .No show-stoppers error occurred . Shut down the old physical DC (with the comment "goodbye old friend" . connected the VM DC to the network and checking for AD replication , DNS and CA ).
9. will perform a normal AD functionality level upgrade .
10. Checked that everything looks ok , performed remote backups for all DC's (disk2vhd) and windows server backup .
11. Succesfully upgraded with no errors .Checked for errors with "repadmin /showrepl","dcdiag /test:replications"and "repadmin /replsum /bysrc /bydest /sort:delta"
12. Schema can be verified with dsquery * cn=schema,cn=configuration,dc=yourdomain,dc=local -scope base -attr objectVersion
13. Be sure to verify in event viewer(on all DC's) that there aren't any errors that might affect AD as a last precaution .