Mentor making me lose points for winning!?

It seems the Mentor ratings are all random. Difficult ones give few or no points and other remove a lot. But... sometimes, even I win on the first try in a few seconds, I can lost around 40 points! Is this known?

Because what you see as difficult may not be difficult for a majority of other users, while things you think are easy, may actually be difficult for most other people. Not sure about losing points for winning, im sure you're probably just mistaken

I haven't used Chess Mentor in quite a while, but I would think that taking a long-ish time on a question would dock points for correct answers. However, if you really are losing points even for solving after only a few seconds, I really don't know what to tell you. Perhaps a staff member might be able to shed some more light on this for you.