LEVEL 16:
wait til the orange platform exactly passes two thirds of the gray vertical bar *downwards*, THEN hit and hold the left key or A, should give you a fair chance to reach the bottle
WHILE LOOKING FOR THE CACTUS COSTUME:
be aware that you don't have to click on each and every cactus, just run around and move he cursor over them, as soon as you find the right one the cursor will change to the usual interaction symbol - saves you a LOT of time!
 "Alxemy"){kind=icon}
 "Mooo!"){kind=icon}
 "Arcuz (Full Version)"){kind=icon}
 "Farm of Souls"){kind=icon}
 "Back to the Cubeture (1)"){kind=icon}
 "You Find Yourself In A Room"){kind=icon}
 "Crush The Castle 2"){kind=icon}
 "Sieger"){kind=icon}
 "Apokalyx"){kind=icon}
 "Epic Combo!"){kind=icon}