Jon I am certainly not the expert here, but if you are successfully logged in as admin you should be able to change your password. If you can't you have some other problem. As a last resort, you can edit the db direct without any problems. If you have any other information on this problem you should share it to get a better response from the real experts here!
I'm working on it right now. I must be missing something in the configuration of the board. I can't get images to work right now either. I use the image button on the top of the message window but the image won't show up. I just get the short cut... I may be trying to do all this too fast. I need to slow down and go through every step one at a time...
Every user can change thier password from the profile screen. Log in as admin and go to your profile. There you should be able to change your password. You will be logged out when you have submitted. You would then have to log in again using the new password.