domain mapping

I'm having a terrible time with this. I've tried it and it doesn't seem to want to work for me. Is there a updated installation file? I'm working with Hostgator and a cpanel... not sure if there's any trick there? I've got two sites set up (using subdomains)

deesbestbooks.misytedev.com
memarketingservices.misytedev.com

and with domain mapping it just get the site sitting there... like its stuck in a loop. I've done a add-on domain with deesbestbooks.com for now, but need to resolve this so I can start using the sites the way I need to. I had pro sites installed as well, but removed it until we get this fixed...

Also, one more question, to set up a google.com apps email for the domain, i need to drop the google file in the root area of the subdomain? do I just put it in the root of the main domain? I can't seem to locate any specific files for the site other than the images folders which are all numbered.