It isn't so easy
There must be edited a script in Launcher to automatically resize all the elements like icons , status bar , etc.
In my port for Galaxy 5 I almost fixed the problems with theming.There is a little dead zone in the topleft corner , icons are too big and lockscreens still doesn't work but is important that we can have status bar , dialer etc.
Thank you very much bravovn for you port.
You are in the thanks section of my ROM and every G5 owner must thank you too for port.