I’ve not done this before, but what you can try is:
1) Log in under old account
2) Make sure Usenapp is not running.
3) Open Finder
4) In Finder press SHIFT-CMD-G (or in menu Go->Go to Folder)
5) Then in the text field enter the following text (including the tilde ~) and press “Go”
~/Library/Application Support/Usenapp
6) Select all the folders and files in the folder that opens and copy all of them to a temporarily folder that is accessible under your new account.
7) Log in under your new account
8) In case you haven’t done, install Usenapp
8) Make sure Usenapp is not running
9) Open Finder
10) In Finder press SHIFT-CMD-G (or in menu Go->Go to Folder)
11) Then in the text field enter the following text (including the tilde ~) and press “Go”
~/Library/Application Support/Usenapp
12) Now copy all the folders and files from the above temporarily folder to this current folder.
13) Start Usenapp and see what happens.
14) The GUI preferences are not copied using the above steps, but hopefully all others are.
Let me know the results, please.