I'm creating a separate topic from this thread: http://world.episerver.com/Templates/Forum/Pages/Thread.aspx?id=19305&epslanguage=en
We have certain pages with a separate property called "PageHeader", and (if set) that property should be displayed as the page link text when using <EPiServer:Property PropertyName="PageLink" runat="server" />. I wan't to create my own control, <MyCustomControl:Property PropertyUsedAsLinkText="PageHeader" PropertyName="PageLink" runat="server" />... you get the point. I have a solution for this that only works for EPiServer 4 (se link above) and need some help to create the equivalent for CMS 5.
Take a look at this code: