Uninstalling flexiWAN is done with a single command, executed from the command line. Make sure to first stop the vRouter from flexiManage, then delete the device from your Inventory.
Execute as root on your device (via console or ssh):
dpkg -P flexiwan-router
After executing the comand above, flexiWAN will be removed.
Make sure the vRouter is stopped before uninstalling the flexiEdge software.