Anyone know how to calculate the range on the senses that these spells give?

just a wild guess, Magic rating of caster or force of spell in meters, which ever is lower?

Same as any other detection spell? Magic * force IIRC?

Looked it up - yep, it's force * magic in meters.

Crap...don't know how I missed that, it was the second sentence for criminy sakes. Too bad there's not an emoticon for hanging your head in shame.