The term open money (all lower case) refers to the concept of user-created "monies". This is described in a number of writings many of which have been collected here.
In this sense, open money is a particular case of open measures (a.k.a.open metrics).
The names openmoney or OpenMoney (no spaces) refer to specific software used to implement open money or, more generally, open measures/metrics.
The current implementation of the openmoney software is essentially a proof-of-concept prototype. However, it includes some important and valuable features that must be retained and expanded upon.
The OM suite described above is very much a work in progress, and is intended primarily as a proof-of-concept demonstration system. This version has been written for use only on Ubuntu (and possibly Debian) and runs Couchbase in a Docker container.
Although Couchbase scales well and can replicate very quickly if clustered, the user-centred design of the OM suite might make a distributed hash-chain system (e.g. Holochain a more natural fit in due course.