At this time this is not possible.
All users would have to own game guru and all media that you would want to use from store bought purchases and also DLC.
What is suggested is that one person enters the final stuff to a working map. These maps can not be live shared at the moment.
Perhaps in time we can add such a feature.
Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz, 2400 Mhz, 4 Core(s), 4 Logical Processor(s), 8gb RAM, Nvidia gtx660, Windows 7 Pro 64bit, Screen resolution 1680 x 1050.
