Hi,
I'm someone who was a part of the team that devised the microbee from its DGZ80 S100 System roots.
I'm here to pass on some knowledge and insight about it and its development from just an idea to a fully fledged product.
The microbee is essentially budget version of a DGZ80 system and was made possible by the introduction of the low power Hitachi 6116LP Static RAMs and the Synertek 6545 CRT Controller, the omission of S100/8080 compatibility circuitry, and the omission of peripherals via the utilisation of software bit bashed I/O. All of the initial software was existing DGZ80 software adjusted to work on the microbee.
If you have a question just ask and someone will try to answer the question as best they can.