A customer had a line chart with square markers on the line. We went to change the size of the markers using the “Appearance” tab under Chart Options. We found we couldn’t make the change stick. We could change other properties (marker shape, line thickness, line color, etc) but changes to the marker size were ignored. So I added a new chart and found the same behavior, which really had me puzzled. I finally went through screen by screen and found that new charts have a check-mark setting in the Chart Expert (Options tab) that says “Auto Arrange”. When this is checked the Marker size on the “Appearance” tab is locked. Taking out the check mark unlocked the property.