Moving site from one sub domain to another [SOLVED]

Yes. Please see the Changing Your Installation Directory support section.

You should be able to move a Showkase site by just copying the complete Showkase folder from one place to another.
As long as the Showkase site was initially installed to a folder of its own, then the entire Showkase site will be self-contained within its folder.
As soon as the Showkase folder is in its new position, navigate to your 'showkase/admin/' folder in a browser and Showkase should recognise that it has been moved and should present you with the setup screen ('System -> Setup').
Check that the 'Path to your web site folder' is correct (it should be filled in automatically) and click the 'Setup' button.
Now just login and your site should be exactly as it was in its previous location.

I recommend that you make a full backup of your site first, just in case anything goes wrong and you need to reinstate your original files at a later date.