Wow, sorry for the very delayed reply
To change columns displayed on the /devices page, you'll need to specify each column you would like. The defaults are hard coded (ie, if you supply no column, you'll get this list). You could also change that I suppose, but it'll be overwritten on next upgrade. I have a ticket somewhere to make these configurable.
To change the URL, try -
[code]http://YOUR_SERVER/open-audit/index.php/devices?properties=system.id,system.icon,system.type,system.name,system.environment[/code]
Feel free to add (fully qualified) properties as you see fit.
To edit the defaults, check the file /open-audit/code_igniter/application/helpers/input_helper.php at around line 870 onwards.
Mark.