Re: Yo, Canadian New Guy.
Good intro post. You've told us a bit about your bike and what's happened with it.
Sorry about your bad luck. Chain de-railments are not uncommon with newbies. Make that motor stay exactly where you put it. Most of us learn this by trial and error. But you can pick up some very good hints reading these threads. You also want to make sure that the drive sprocket is installed well. Straight and true. Beware the chain tensioner; it can also destroy spokes.
Elbow (and knee) pads are a very good idea. When doing any real riding, I wear 'em. Plus gloves, decent boots and a helmet. Maybe I look like a dork, but that's very, very low on my priority list.
I'm afraid that I didn't understand the bevel drive gear that you mentioned. But the answer to your other question is 'yes'. Unfortunately parts do break on these china girl kits. They are just not super high quality. But, like an old Volkswagen or a Chrysler from the 60s or 70s, they're still (strangely) lovable.
My answer to the parts issue; a second motor and kit sitting in my attic. Basement might not be a good idea; too moist. When I need a part I take it out and then order that part from one of the vendors that you'll find in the margins of these pages.