The system prefs control panel settings do have a bearing on what you can capture. But you don't have to specify resolutions on the control panel - just signal formats etc.
Change the control panel settings as required first - BEFORE opening catalyst
Then you should be able to select resolutions in catalyst input control HUD
I think theres an issue with 720p in m257 [ no there isnt - samsc ] - but PAL/NTSC and 1080i should work.
Note that Intensity PRO only supports 1080i not 1080p [ this is an hdmi edid thing they have to talk to each other - samsc ]
Dont change system prefs blackmagic settings while catalyst is open.
Simon