Dara,
I recently discovered that Microsoft Excel has an evolutionary search algorithm in its Solver utility.

It may be instructive for others to try it out if they have time to experiment.

I tried it out on a parametric version of a differential equation, whereby the x''(t) was approximated in place as double differences between adjacent cells.
Then I set the DiffEq error between the LHS and RHS and minimized this error with the solver. For now I used the sum of abs(error)

It does get close to what I get with the full DiffEq solution but I will have to keep on experimenting with it.