Cant complete hospital

Im to the end of the hospital level - I just need to press a green button but it wont register. Little white dots blink around he button but if you click on hint the button does not light up with purple like other interactive areas. The valves are set correctly and Ive done everything else. Its very frustrating to get to this point and not be able to continue on with the game!
I also second others complaints about trying to click on the inventory button - almost impossible sometimes. Looks like a food game but too difficult to use.

Boxcrazy about Mystery Case Files: Escape from Ravenhearst Collector's Edition - A Hidden Object Adventure