Building on someone else's land

OK - now I'm getting ahead of myself.
I want to stream the video in a previous blog on to SL. So I've gone through the help section (rather long, again - not at all intuitive) and have worked out I need to build a screen first to show it on.

So I try to, but as it's company land and not mine, I'm not allowed to.
So shall now wait and see if I can get permissions.