I installed v3 right over the default one from nokia without a problem, (running cfw from niceoni)
I tried this way of installing because i have my own theme with over 50 converted pictures and didn't want to lose the selfmade theme.
The added pictures however make me realise i don't really need my own pictures anymore as these new added are great also
good job +1 !
Maybe it's because i have open4all in rompatcher in my autostart to have acces to all folders all the time, but for me installing this didn't demand extra install options.