Yes the system is completely standalone and will work with any video sharing script. I use the existing template to demonstrate how well it integrates into existing system. Besides that i have noted that unlike joomla and wordpress, PHP Motion is unable to provide a pure mvc architecture, hence templates are very much dependent on output of the php file.Hence to add a menu item to template you need to edit every template which is not good programming. As for the subdomain installation thing, this is only for demonstration and not for use of the php motion script or for sale. I believe you can install wordpress on any subdomain to try it out without any copy right stuff.
You buy: Swf recorder + backendphp script as a package
We integrate it into your template/system for you.