I have the same machine and you can have the excess hanging out the back. Eyeayen is right on the A4 thing, width is the limit not length.
Im still struggling to find decent decal/sticker paper? I can do basic stickers, but not decals, at least not any with white in them.
I bought a couple of cars off a mate, both have cracking decals with white in the layout, I have asked on the forums before but got no answer on where to get that kind of decal paper.
Still not interested in 'doing them' for anyone, just want to experiment on my own gear and it would be daft to pay for something I can do myself.
BTW how small a cut can you do on the Robo fella?