To add to Gary's response, new software is given out privately to beta testers and they test everything they can. Once the beta is given out publicly to the masses it's tested even more by many more people. That's one version and is an even numbered version like 5.02, 5.04 etc. Anytime bugs are found they are fixed and the next public release is the next even numbered version. We are now on 5.06 so that's only 2 revisions from the release of 5.02. Be thankful that a company like Centroid is on the ball fixing and releasing software all the time unlike other CNC software companies.
This is why everyone is asked to be using the current version as its release not only introduces new, amazing features, it also fixes issues or bugs in previous versions.