They're great cameras.
To help prevent the fat roll problem, you can bend the metal springs in a bit. If that does not work, try a piece of foam, like a Holga comes with (but always falls out) or a loosely folded up matchbook or 120 film box with room to compress as the roll is filled up.
Be careful, as the wood to which the metal spring is attached can be fragile. It can snap off without too much effort.
You also might want to start taping up your rear window, and uncovering it only briefly in the shade of your body when it is time to advance the film.
FWIW, if you have a three-aperture model, your apertures are f/11, f/16, and f/22. If you have a two aperture model, they are f/11 and f/16.
Your shutter speed is probably about '25 to '50, or at least it was originally.
The lens is about equivalent to a 35mm focal length lens on a 35mm camera.
There is a Brownie group here on APUG.