click on everything you can. not only do you have to find the monkey, you have to free him. if you can't open the cage with the key then make sure that your mouse is touching the cage.
do not read this unless you have completed the game! it took a while for the cloth and key detection to work, but I eventually got it when I added a 0 second delay to the "go to" blocks. also, it took me a whole day just to do the art.