Using version 4.1 on Windows 7
I think I've narrowed down the ToolBar disconnect problem mentioned with Version 4.0. It appears to be associated only with the FlowField category and only when the number of checked FlowFields is 1 or 0.
Here's how to replicate.
1. FlowField -- uncheck all but 1 FlowField
2. WaveShapes and ColorMaps -- uncheck any number. You can even uncheck all configs or check them all.
3. When you exit and try to reboot, the ToolBar will not be attached.
The same problem appears when you uncheck all FlowFields. So anything less than 2 FlowFields will generate the disconnect. The same problem does not apply to WaveShapes or ColorMaps.
The workaround is to always have at least 2 FlowFields checked when you exit. If you are constructing WaveShapes and prefer to have (Empty) checked all the time, clone (Empty) and rename it.