MoI5beta custom Background color, or Gridline color, or Accented Gridline color,
are inadvertently transferred to corresponding MoI4 color settings.

Open MoI5beta (May 22, 2002 version).
Go to Options > View > Background color > Custom, and change the color, say to Blue-ish color.
Close MoI5beta.
Open, (or Close and re-Open) MoI4.
MoI4 background is now Blue-ish.

Similarly for Gridline, or Accented Gridline Custom colors.

Hopefully this is similar to the CustomUI screen capture bug?

- Brian