• reconstructs the disk subsystem, leading to improvements to the 8272 and to floppy drive emulation across the board;
• implements write support for HFE files;
• switches to a platform-neutral system of keyboard mapping, simultaneously correcting minor errors in the CPC key map and adding missing keys to the Vic-20;
• ... including the restore key, which is notable because it is wired up to a VIA control line and thereby can generate an NMI;
• corrects access alignment mistakes in the Electron and CPC video subsystems, giving a minor speed improvement on x86 and making the code much more likely to function on other architectures;
• corrects various other accidental uses of undefined behaviour, mostly related to variable initialisation, and ports a central piece of timing to C++11;
• corrects potential start and end of line artefacts on the Electron's display; and
• includes very minor 6845 accuracy improvements. But it's not there yet.