It is mean to 'crash' (well, turn off or freeze[in which case turn it off yourself after 15 secs or so]) once you have viewed the image.
Turn the psp back on and try to run the 1.5 update, you should find the downgrader has done its work and the 'update' will run. All the 2.0 downgrader does it make the psp think its a version 1.0 to allow the official 1.5 update to run.
When the 1.5 update gets to 99% or so it will crash. It will then either do a restart by itself or will sit there. If it does nothing once it crashes at 99% then just wait 30 secs or so and turn it off.
When you turn it on again you should see an sony error message about your settings being corrupted and needing to be reset. Press x to continue and welcome to the world of homebrew-capable psps.
