The first time you run HIDE you may see 1 to 4 windows open, depending on the initial setup of your current version.
At the very least, the main window (the one with the menu-bar) will be open. The visibility of other windows may be altered by selections in the View menu.
The windows may be in either floating or docked mode.
Floating windows reside outside the main window, while docked windows will be within the main window itself.
Whatever changes you make to the window positions and status will be saved and restored the next time you start HIDE.