Get JPXS Free Flash Decompiler, open up the Habbo.swf. Goto IMG 12 and 13. Right click the images and click export. Then edit them and replace the images.
You must be registered for see images attach
You will also need to replace the camera images. I'm sure you could just edit the SWF to show one image instead of all 3 at once but I'm not sure on that.