Havent read what your trying to do exactly.
But heres a curve ball....
One possible solution is to buy a couple of cheap ebay remotes.
Disassemble/ rig up to comp or small circuit board with timer.
Then set to fire infra red remote at wanted shot intervals.
Camera can be left in any mode to take the shots.
I say a couple of cheap remotes ... as there cheap ... some may die in the mod process.
Alternatively just leave remote alone... clamp it next to programmable lego or similar that just simulates the pressingof the button.
All the best ...