I do have the same problem:
Synology 1511+ (Intel based) , DSM 4.2, Video Station works and recognized my HdHomeRun (older version, with two inputs)
I installed TvHeadEnd package from www.synocommunity.com. Video Station is still running.
When going to the configuration, the Tv Adapter combobox is empty....
I'm using Over the Air Antenna (ATSC) but that shouldn't matter yet.
Any help is welcome!