I managed to get both stars without using B! But there are one too many blue bots to get any further. I even tried lowering them to the level underneath but that made it impossible to get past them.
Forgive me, I thought of a way to win! It worked beautifully! Good one. Spoiler: My solution I moved all the bots down using the lift. i then let the red one go onto the steps and into the water. Luckily he stays at the side! I had hoped to do the same with the blue bots but found I could pass them easily. From there it was plain sailing!
