I've spent the last few days working on the Small C compiler, the Flexemu (for Linux - https://github.com/aladur/flexemu - requires a lot of QT dependencies which are not well spelled out) and the FreeDOS/Dosbox emulator. I have a Debian setup so I've been getting all of this working on my new Linux x86 system (old one crashes - hardware issue). I also use Mike Evenson's Memulator (http://www.evenson-consulting.com/swtpc/downloads/) which emulates a SWTPC 6800 or 6809 (Flex, OS-9, etc.). Finally I spent some time with the Pie editor. Still need to learn more about that one and see if I can get it assembled for the 6800. Things are slowly coming together.