I would like to have a DynamicModule (in a palette) with a Checkbox that controlled a Global` variable and that would in turn indicate the state of the Global variable if it was changed from within the notebook.
Actually, I can do that, but I would also like it to survive quitting and restarting the Kernel - while leaving the notebook open. That I don't know how to do. The actual problem is updating the DynamicModule variable from the notebook. So here is a simple attempt where all I try to do is update the DynamicModule display from the notebook.
If I evaluate one of the systemState cells and then the DynamicModule to create the dynamic display cell, I can flip the display back and forth by subsequent evaluations of the systemState cells. If I Quit the kernel the display changes to 'systemState'. If I then evaluate one of the systemState cells, restarting the kernel, it behaves properly (for me) and I can again flip the display.
But if I Quit and restart a second time it won't work. If I copy the dynamic cell it works and if I close and reopen the notebook it works. But I don't want to do those things and I don't know how to reliably recover from just quitting and restarting the kernel.