Navigating between the different areas in Xcode with a keyboard
The shortcuts you are looking for are the following


The project navigator is: ⌘+1 (Cmd-1)  
The issues navigator is: ⌘+5 (Cmd-5)  
Main Editing area is (once you have selected a file in the
issues or project navigator):


⌘+J (Cmd-J) and, after release, ↵ (Return) or  
⌥+⌘+` (Opt-Cmd-`)  

The Mini Map: ⌃+⌘+⇧+M (Ctrl-Cmd-Shft-M)


Hope that helps.