How to globally specify/parametrize a soapui project -loadui

Hi
I would like to specify, for all soapui runners inside a loadui-project , the soapui project file and the environment specific config xml/groovy files. How to accomplish that in loadui, so that there is a way to switch between different environments in the same instance of loadui.

Also, I noticed that when soapuiRunners are run for the first time , loadui creates an xml file by itself with the same name as the soapui projects directory. Could you please shed some light on how this works...

Thanks!