I need a little more brain power than I can muster right now.

I am replacing the upload data type with a custom upload data type, and in some cases creating a secondary type that will just have a text string.

Anyhow, once these have been changed, the files no longer are available to be linked in the tinyMCE link dialog.

I dug into code and found that GUID's specify which data type can be used in links, and that these are in code, and not in any config file.  The documentation on the propertie state to either override the tree or to add the guid to the list (LinkableMediaDataTypes) on application start.

So, my question is this:  How do I add a GUID to this list on application start?  Further, would it not be easier to add this into the configuration files for umbraco for v4.1?

Anyhow, if someone has any information, I would greatly appreciate it.