Version 5.9.2 of Poly/ML has now been released on GitHub. It has been almost two years since 5.9.1 was released and there have been a few bug fixes since then.
Probably the biggest change has been with the conversion from floating point to strings and digit sequences. The old Gay code has been replaced by the Ryu algorithm coded in ML.
There have been a few fixes specific to Mac OS. In particular the object code exporter has been changed to deal with a problem with the Xtools 15.
There are a number of pull requests outstanding so it's likely that the next release will include some bigger changes.
David