So , I played this yesterday and it took me some time to figure out where the Emblems and Bananas are hidden.
In case anyone else is looking for them, here are my findings:

Clown Emblem - Easy, click on the button that appear inside the Elevator during Phase 2. The Emblem will then appear on the 10th floor button.

Crow Emblem - Pick up the crow on the 40th floor. Collect the Maraccas on the 30th floor and hand them to the crow.

Magician Emblem - It's on the tenth floor.

First Banana - Easy, click the plant a few times and the banana drops out of it.

Second Banana - That one took me by surprise. While in the Elevator, open the options menu. The Banana hangs on one of the options. Seriously.

Third Banana - 10th floor; remember there's a special ending with the crow and two bananas. So don't take the crow if you aim for an ending that requires all three bananas.

In case you havn't figured out how to either get the cat or the crow:
Enter the 50th floor, keep the umbrella closed or close it again after interacting with it. The cat will then be inside the present of the 40th floor.
Open the Umbrella at the 50th floor and the crow will be inside the present on the 50th floor.
Skip the 50th floor and a Jack-in-the-box will be inside the present.

Have fun finding all possible endings.