Few changes and bug fixing. - Subtle decorative arrow when selecting new body velocity vector (mimicking planets' ones) - Using 2px minimum body radius when rendering. - Made Pause state more prominent with a border and a "PAUSED" caption. - Fixed crash when using RK methods after version 0.9.1 - Fixed crash when exchanging solver in some circunstances. - Fixed Spinner bounds logic. - Other minor fixes and changes.