ok, well this is pretty simple ... If you check the SOURCE of those two documents, the only difference is the following:
flashVars.contentfolder = 'content/private/urbanagent/';
If you ADD that code to your manual "something.php", then you have the contentfolder hardcoded.
However, of course currently you can't call it "index.php" because your main imagevue gallery is using "index.php". If you were gonna change that, you would simply change the contentfolder in the GLOBAL settings in admin...
If you are going to create a new folder (as you call sumbdomain), you will need to make sure to reference the SWF correctly, and you should be creating a HTML file instead of a PHP file (or else you will need to do several changes to the PHP file).