Bobby Bearing - how to complete?

[blackdalek]

Another game I remember spending hours playing back in the day was Bobby Bearing.
Once I found them, I never could figure out where to roll Bobby's "brothers" to in order to rescue them, so I always ended up just killing them and moving onto the next one.
I recall I had an infinite time cheat for it, and still couldn't figure out how to complete the game.

[ervin]

Here's a walkthrough of the spectrum version.