Powerpoint under C# automation + Thumbnails

Before i try to re-invent the wheel, the following is what i want to do :

Context - kios situation

- Run powerpoint showing thumbnails at the top or bottom of slides to come /
been
- Slides by default transition on fixed time
- However i have a USB button which i have C# s/w which allows me to read
presses. A press and hold will hold the screen (up to a much longer time) and
a tap will advance to the next slide.

I have reasons for using powerpoint over flash, due to dynamic content
update.

So unless there is an addon that does this and allows me to run my C# button
code i need to add it. The slides under C# i think i have covered but what
would be handy would be examples of converting powerpoints to thumbnails like
what some browers do.

Thanks in advance.