Started on the gameplay

The attract mode screens are complete so it's time to move on to the actual gameplay. I'm loathe to get too far into it before I finish the RE, but I've found the transcode/test cycle is helpful to RE the code. So as long as I'm not including swathes of unknown code, I'll continue down this path. At this point I'd expect visible progress to slow a little as there's the inevitable setting up of game data before anything interesting happens on the screen. And this game data is largely un-RE'd at this point.

But here we have the gameplay screen initialised together with the player frog sprite.