actually, 2-3 is too much. One task was labirynth, that is around 1.5, and the other one was collect titanium with optional additional task of collecting nuclear cells (and killing spiders to do so), so the simplest possible solution is somewhere around 1.5 too.
And speaking of depth, how deep into CBot competitors need to go? On scale from 1 to 10, where 1 is simple "Find Titanium" script and 12 is Omnipotent hyper program which can solve every mission in regular campaign all by itself?