Hi There,

I use MIDI to control various other things on my computer using two programs.

The first is Bome's MIDI Translator. This converts incoming MIDI messages to
keystrokes (I have mine assigned to all the windows key commands as I don't
use them).

http://www.bome.com/midi/translator/

Then I use Auto Hot Keys to assign complex macros to those key strokes.

http://www.autohotkey.com/

For example you could set a script up so that when MIDI CC value 1 on
channel 10 is recieved, bomes sends the key stroke [windowskey+q].

When Auto Hot Keys picks up the [windowskey+q] command it excutes a script
which could do something like

Focus on powerpoint
Push the right arrow left three times
wait 20 seconds
push the right arrow left one time

Hope this helps.