IntelliJ Split Window Navigation

It looks like it's now mapped to Alt+Tab and Shift+Alt+Tab so no need to remap (at least for OSX 10.5+ settings).

Ctrl+Tab and Ctrl+Shift+Tab for Window | Goto Next Splitter and Goto Previous Splitter. However, these hotkeys may be taken by the Switcher, so you need to remap them in Settings | Keymap.