Thx though I just find out the problem is ...Its my mods file...1.7.2 and 1.6.4 shares the same mod file..I installed 1.7.2 but I still have 1.6.4 mods...Once I delete all the mods it worked....
yeah..but even if there is no red stone...it is still on..you can try in [1.7.4][1.7.5][1.6.4.]..if u do it in certain order,
1. place the lever and turn it on 2. put down the piston
When I am making a map there is a hidden door that have to be activate 2 blocks down from the lever, I can never get it right because of this weird thing here..