@jinsalaco:
1. For post navigation, you can add the following css in “Appearance => Theme Options => Custom CSS” box:
#nav-above { display: block; }
#nav-below { display: none; }
2. Regarding Support, I treat both equally as support is very important. But supporting pro theme in easier as there are lot of features on and it’s more stable.
3. There are lot of additional features in Pro version, which you can check out at theme instructions page at http://catchthemes.com/theme-instructions/catch-kathmandu-pro/