I mostly deal with the possibility of bricking a device by not caring too much :) That said, I usually start by reverse-engineering the software at one of the ends, so I don't blindly "fuzz" the device. There's still some risk, but not that much.
replyI don't have a Cameo Pro 4 to test, but I have reverse engineered software to control some of their other devices. It's a little janky but if you want to help I'd appreciate it!
replyI believe there is (or once was) also an Inkscape plugin somewhere but I never tried it.
As for how I reverse engineered it, I just used a USB sniffer and wireshark. I don't think there's a big risk of bricking these devices - I don't think they even have non-volatile storage, so worst case you turn it off and on again.
I would like to reverse engineer my solar power inverter too, but that is definitely brickable (the first one they shipped me came pre-bricked!) and is a lot more expensive so I've had to resist. :/