What papalonian said is right, when this machine came out it was expensive but as today standard, this machine isn’t worth much so don’t spend a lot of money on it. Every plastic part that you see can be printed with your printer. Should be available in their GitHub page. Nonetheless, it’s a great printer to learn 3d printing

Haven’t read so can’t tell you but you will find info at https://leminal.space/post/11699480

Cura can ignore what’s below buildplate as long as part isn’t too big for X Y axes. For cutting this, I would use 3d builder. Very easy to use. Just open model, and go to modify to cut model

Can second that email works great to send Epub, never had issues in years