I've spent the afternoon avoiding the Options menu. I really hate UI coding, it's so full of potentially tricksy pieces.
Instead I've fixed all the niggly bugs and added explosions to ship deaths, including the player, with a seconds worth of delay after dying so you can watch the remains of your ship fly into the unknown.
So yes, everything is now drawn correctly at the edges of the Arena and I've removed those horrible red lines. Passage between one edge and another should be unnoticeable.
I've made some minor changes to balance.
Enemy ships now have a variable amount of shield power depending on the wave. Up to wave 5 you'll always insta-kill them. At wave 6 they'll take 2 shots, at wave 11 they'll take 3, 16 they'll take 4, etc.
I don't think there's anything else to add at all to the game itself now. Balancing tests still need to be done, but I think that should be fair enough. Getting past Wave 11 will require considerable skill I suspect, but that was true on the original Foray as well. I think the furthest I ever got on that was around wave 15.