I had to update a password manually and ran into some issues. The invoice system for American Airlines doesn't play well with Safari, and I have to use IE through VMWare Fusion to access the site. I can reproduce this error all in OS X though. Running 1.6.3 and 1PW 3.1.3 (build 30645)
Create a new login entry
Type in a password (I use "test")
Click on the "Generate" button to the right
Side note: the strength bar and copy button are inside of the pw field, some sort of draw error. It moves higher every time 1PW loses focus and then regains focus. It's very slow moving, but if you alt-tab a few dozen times you can see it. Only way I could reset this is to quit 1PW and restart.
Notice the randomly generated password
Have 1PW lose focus (I hit "copy" so I could see if the password would be accepted by the AA system)
Refocus 1PW, notice that it generates a new random password
This is the first problem -- I was making sure the AA system accepted my password, and then I would save it. A combination of having the clipboard forget the password after 90 seconds and the next issue caused me to lose the new password and request an email reset.
With any password generated, click "save"
This is the second problem -- the login password does NOT get changed with the new password, nor does an entry get created in the "Generated Passwords" area.
I've since turned off the clipboard security which lets me test the password and then copy it back into the password field for the login.