There are instructions about the 507 error in the first post of this thread. If the 507 thing happens (it does occasionally, even to me) you will lose 3rd party apps. You'll have to reinstall them.
I just posted a backup method for 3rd party apps today in the RIM Software forum. Might help for next time.
To get the browser you'll need to register the device. Go to Options >Advanced Options >Host Routing Table >Menu key select Register now.
For Password keeper you'll need to plug the device back in, go back into application loader and check the box. Check to make sure the other application boxes are checked (for the ones you want,) as well, while you are there.
Edit: I changed the first post of this thread and added a link to the instructions for backing up 3rd party apps. Better late than never....