Hi Manu!
I'm glad you enjoyed it, and thank you very much for the feedback! As this is my first game all feedback is greatly appreciated.
Are you referring to the levers room? If so - there's actually a hit for the solution in the room itself! One way of solving it is, as you did, actually "calculating" which levers you'll have to have on; but you can also follow the hint in the room. It's a bit more hidden than other hints, but it's there :)
Thanks again!
Ev