I'm also trying to achieve this same functionality. I'm using smart search for our website as a whole, but I would like the search results to show both pages and our press releases, which are housed in a custom table. I set up the search index for the custom table, added it to the webpart, and I tried to implement the code used above for the transformation, but I either get a "The name 'GetSearchType' does not exist in the current context" error. I'm using Kentico v8, so perhaps this code is outdated?