Hmm no. Visionaire 3.x license key was only valid for all versions of Visionaire Studio 3.0 until the final public release of 3.x (3.7.1) before 4.0 beta was released. The 4.0 license will cover all future builds from 4.0 beta until 5.0 is released & then you will need a new license to upgrade to 5.0. So yes, you need to purchase a 4.x license to upgrade to 4.x builds. There's lots of new features for 4.x such as windows/mac editors, multi-platform export support (win, mac, linux, ios, android) & various new action parts, open gl shader support, new lua functions, new sound engine, various optimization edits & bug fixes, 3D character support (early days) & whatever else has been added/changed. I forget.