Jeannie, Lucy seems to get the point. Not all the versions of a software product are available to public, especially the Pre-Alpha builds, which are usually available to the developers inside the company. And also, whenever the developers make a new build, they would name that build with certain code, which is probably why we don't see version 10.0.0.1 and 10.0.0.5. However, I did check their forum, and I saw there was the 10.0.0.0 Alpha made available to the public testing.
Hope my explanation kinda of help you understand how developers manage the version numbers of a software product.
BTW, I like the GUIs a lot, they look pretty concise, especially for the Creator modules, all the necessary settings can be completed at the front window, you don't need to click Next button and Next button again...
Also, the new changing skin feature brings us some fun elements here, although it's not a big deal, it really means something to part of the users. To me, if only I were allowed to upload my own picture as the skin, that would be perfectly interesting!