The program uses the file DEFAULT.RWS at Open File. You can change the RB Windows Setup to suit your own requirements such as which windows your want open at the start, by using File > Window Setup > Save Window Setup and overwrite the existing DEFAULT file.

In addition, you can save a copy of your setup as Favorite.RWS, which should take preference, and save as $Options.seq the latter being useful when your require to start a new file.