1. I plan to have both the Window and Scene Visual Editors in the Demo.
2. If I can manage to get a copy of RMVX, then I promise a second version for use with RGSS2.
3. There will be no need. Since there is no way to edit source directly, there is no need to test code. It will always work! But you have to keep in mind that the current version concept has removed the entirety of the Event-Coding Editor. You can only place windows, setup a Scene, and select several options that will make things easier for the User. The real meat of the script will be done by hand in RMXP/VX by the User.
But the User will get some short cuts, like deciding what a selected command does in a command window, whether it be calling another scene or moving the window, or making another window active for use.
Glad to see interest still lives in this. Peace.
~OS