Can I change the symbology or colors on the maps?
Basically, no. Because ArcReader maps are “published” maps they cannot be modified. However, ArcReader does have the functionality to change the color transparency of a data layer. Changing the transparency can allow you to see more or less of the data layer beneath a particular layer. Simply right-click on the layer you wish to change and select transparency. Left-click on the slider bar and change the percent transparency to the desired amount. Note: changing the transparency causes a change in colors on the map that are not seen on the map legend or the Table of Contents.