Created a better video recording approach by just recording the drawing primitives at the engine level. This allows to create nice 60 FPS videos from now on :)
The following video shows the GUI system, it is scalable without losing crispness (in fact it uses subpixel high quality antialiasing everywhere) so very well suited for productivity with the editor. The 2D rendering is shown in software renderer but a high-performance GPU rendering also exists that can render complex 2D shapes with the same 64x subpixel antialiasing.
The rich text panel is something that is not as optimized currently. I've ported it from some other project of mine because I thought it could be useful for some things (like integrated help in the editor). The majority of slowdown is because it redraws everything needlessly on change and also because all the text rendering is done by rendering 2D shapes :) This is because it uses subpixel positioning so it's not as easy to cache to images. For normal usage in GUI it performs well (esp. on the GPU version).