Visually, the application may need to be updated but your V8 code will probably work just as well under V9 as it did under V8. All you really need to do is update the GUI - button sizes, icons, fonts etc.
You may need to make use of some new start-up parameters such as -extravc (extra value changed) so that your browsers continue to work in the way they did originally. But overall, the upgrade should be pretty painless.
Now, if you also want to update to ADM2 then that's a different matter. In my opinion, if you want to do this then just rewrite your application. You may be able to use the conversion tool that PSC supplied but I wouldn't recommend it.
