The poster's from Europe so I'd suggest they're after JAA requirements.
My company/aircraft don't allow for planning a single-engine landing in conditions less than Cat 1. That said, if we have an engine failure at a certain point during an LVP approach we're allowed to continue to landing i.e. the aircraft's capable. If the conditions are below Cat 1 at the departure airfield i.e. precluding a single-engine return, we nominate a Cat I takeoff alternate (within 400 nm or one hour's single-engine, still air, flying time, whichever the more limiting).
B&S