What do I need to replace Cranium: Turbo Edition's electronic timer?
From the Turbo rules, the electronic timer lasts 60 seconds. This is the same as the egg timer in the base game.

I can't speak to the colour probabilities or guarantee that there isn't a mechanism to (for example) ensure that a mix of colours comes up, but I think uniformly randomly choosing a colour is a fair and fine way of doing it.