Change entry in selection windows to something other than up/down arrow?

I use the IdeaVIM plugin and for the most part I like it.  One of the things that bothers me however, is when I have to select something.  For example, if I hit Ctrl+Shift+N (go to file).  I may type out 3 letters and then see a list of options.  In order to choose this I have to remove my hand from the homerow and move it down to the arrow keys to choose.

It would be really beneficial if I could either

a) use tab/shift+tab to do this, or
b) define another set of key combinations for moving up and down in the list.

Is this feature available?  I couldn't find it.