If you look in the default.html template file after <%-- DAY VIEW --%> tag, find the line
<TD CLASS="thinborder" BGCOLOR="<%=$_GRID_CELL_BGCOLOR%>" VALIGN=TOP>
a little ways below it.
Try inserting the following code in place of it:
<%IF EVENTS EXIST%>
<% $cellcolor = "#FF0000" %>
<% ELSE %>
<% $cellcolor = $_GRID_CELL_BGCOLOR %>
<%/IF%>
<TD CLASS="thinborder" BGCOLOR="<%=$cellcolor%>" VALIGN=TOP>
Hopefully that should color the background of cells with events in them in Day View and Grid View. If you wanted them colored in 'List View' as well, you'd have to modify the code in that section in a similar (but maybe not exact) fashion.
This code is un-tested so use at your own risk!
Dan O.
[This message has been edited by DanO (edited October 12, 2003).]