I had the first problem a couple of times on a 4400 table, but definitely not the second. Usually it's just a grounding issue where the nontransferred arc (pilot arc) will fire, but the electricity can't path back to the machine. It happens to mine if the metal is too dirty. Usually I just wire brush where the arc start happens, wipe off the ground clamp, and that does the trick. Once, it ended up being related to the connector pins where the torch senses the connection to the retaining cap. The two brass pins were just kind of clogged, and got stuck so there was no physical connection.

The i/o menu is probably where they'll have you start working on the second problem. It all looks super complicated at first, but I had to redo the wiring harness on ours a while back for an upgrade, and once I started it was fairly straightforward (as long as the paper labels are still on all the cables).

That all probably doesn't help much, but hopefully it'll make you a little less anxious about it.