Problems installing and using Exchange 2007

I'm upgrading my Exchange 2003 organisation to Exchange 2007 this weekend, as a reinforced learning experience for when I begin to deploy Exchange 2007 for a major customer.

I had a couple of problems:

1. A setup error occured: "[ERROR] Access to the path 'D:\Setup\ServerRoles\Common\64' is denied"
2. When I re-ran setup, it installed, but there were no routing group connectors between the old routing group "First Administrative Group\First Routing Group" and the new routing group "Exchange Administrative Group (FYDIBOHF23SPDLT)\Exchange Routing Group (DWBGZMFD01QNBJR)".
3. I created the routing group connectors, and moved a mailbox, but mail would not flow. Kept getting 5.7.1 Relay Denied errors from the new organisation.

I found a few references:

Setup error:
http://forums.microsoft.com/TechNet/ShowPost.aspx?PostID=2746265&SiteID=17
http://support.microsoft.com/kb/943507/en-us

How to install Exchange 2007 into an Exchange 2003 organisation:
http://technet.microsoft.com/en-us/library/bb124350(EXCHG.80).aspx

How to remove Exchange 2007 roles:
http://technet.microsoft.com/en-us/library/bb124115(EXCHG.80).aspx

For some reason, my new Action Pack came with Exchange 2007 SP0 and not SP1.
I've downloaded Exchange 2007 SP1 and will reinstall this when I have removed Exchange 2007 from the server.

Exchange 2007 SP1:
http://www.microsoft.com/downloads/details.aspx?FamilyId=44C66AD6-F185-4A1D-A9AB-473C1188954C&displaylang=en

Exchange 2007 SP1 Release Notes:
http://www.microsoft.com/downloads/details.aspx?FamilyId=5770BD59-376E-42EC-B940-BE6225CD97FF&displaylang=en


NB:Just what does FYDIBOHF23SPDLT and DWBGZMFD01QNBJR mean?They are shifts of "EXCHANGE12ROCKS". First one, add 1 to each character, second one, deduct 1 from each character.