I also have X5 and have produced both WinHelp and Microsoft
HTML Help. You did not specify your output, but there is an option
from Project view in both help formats by which you can open
Windows and adjust the placement and size of the help window. From
WinHelp, click the Project tab at the bottom left of your screen.
Then, from the list of options on the left of your screen, click
Project, Windows, Main (by default) to open a window in which you
can rename the window, establish which window/s open, background
color, position and size, etc. From RoboHelp HTML, you can click
Windows in the list of options at the left of your screen and
follow a similar procedure. Hope this helps. Regards.