Can you give more hints? I tried picking up the green/cyan/grey balls & was only able to pick up the grey. Can then place this in the centre of the 3 crystals and get a different colour depending on what the 3 crystals are set to. But I can't see what to do next. Can't place the re-coloured ball on the empty plinth. Still can't pick up the green or cyan. I've read the two plaques as well. Setting the 3 crystals (holy trinity?) to R/G/B (or R/G/clear) gives Gold but still can't do anything with it.