Dynamic Chart w/ ComboBox Issue

In my attached sample file I have a set of data that I am charting dynamically using a form comboBox. Problem is that there is no way to change the font size unless I use an active x comboBox. Problem is it is not liking my offset formulas when I switch to the active x ComboBox. I've tried numerous workaround and no luck. Any help would be greatlly appreciated as I need to change the font size in the combo box for a project at work I am working on.