I could not understand completely what you mean. You want to make only the titlebar of the dock transparent but to leave its content solid or you have something else in mind. What do you mean under "the dock to remain transparent"
? Please, explain in more details what is the result you want to achieve.
If you want some part of the RadDock to be transparent but another one not you can use the css class selector related to the corresponding element and add the needed settings to this class. For example, if you want a transparent titlebar but you do not want the dock's content to be transparent you can use the .rdTitlebar
|<telerik:RadDock id="dock1" runat="server" style="" text="RadDock1" title="RadDock1"></telerik:RadDock>
More information about RadDock's css classes you can find in the CSS Skin File Selectors
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