I just published the first build of V5 at http://www.grzsoftware.com/v2dl.php . This includes lots of internal changes to support the coming V5 features as well as:
64 Bit Support
A new “Automatic Toolpath Wizard” in the main toolpath dialog
I have been using only this version for about a month and it seems at least as stable as V4 although I’m sure there are plenty of bugs in there. I would like some feedback on the new toolpath wizard if you have some time. The main purpose of it is to analyze the geometry and then enable a “sane” set of toolpaths so new users don’t have to know what the difference between waterline, pencil, and parallel finishing are.
I am already getting upgrade questions so I just want to reiterate the upgrade policy- if V5 is released within one year of your purchase (either a new purchase or an upgrade from a prior version), you will get it as a free upgrade. I can guarantee that it will be released in less than one year from today, hopefully much sooner.