Grimstonefire:
It’s the definition of ‘hit as normal’ from the ravening hordes list that is the tricky bit. Whether to go with ‘as normal’ meaning shooting in open terrain (which makes no sense), or ‘as normal’ as in following the rules as they were/are written about shooting at targets behind cover.
Normally all missile weapons are at -2 to hit against buildings, so Imo it should be played as hitting on a 6.