How do you replace BDC URLs from the “Site” search refiner?

Question

We use the BDC to crawl data and modify the search results to hide the URLs from the Core Search Results web part. However, in the Refinement Panel web part there is a "Site" refiner that shows our BDC URL. If clicked the BDC url for the refiner URLs in the refiner start looking even worse.

I was hoping to modify the Filter Category Definition in the Refinement Panel web part to replace my bdc URL with something more meaningful. However, a straight replace doesn't work for me. Below is an example where I tried with character encoding for ":" and "/", but I tried without encoding those as well.

<CustomFilters MappingType="ValueMapping" DataType="String" ValueReference="Absolute"                 ShowAllInMore="False">
  <CustomFilter CustomValue="My New Value">
    <OriginalValue>bdc3%3A%2F%2Fmy_old_value%2Fdefault%22</OriginalValue>
  </CustomFilter>
</CustomFilters>

Any ideas? Even if I can replace this one "site", I still have two problems:

1. The other sites are not shown. I guess I have to enter an for each of those, but I won't know those ahead of time. I was hoping that if they were not listed that they would just not be modified.
2. If I click on my site's link in the refiner, it will still likely show an ugly URL underneath it. I really need a "Relative" ValueReference and use wildcards or something. I have only seen relatively value references with dates and numbers, though.

Answer 1

It looks like the answer may have to be to extend Microsoft.Office.Server.Search.WebControls.ManagedPropertyFilterGenerator and override it to handle our BCS content properly. Far from an ideal solution.