Can coloured coins be given to miners?
Although it's not covered by the specification, it seems logical to match all transaction fees (in the order in which the transactions appear in the block) against the block reward the same way other transactions are matched. The leaves only whether the block reward comes before or after the transaction fees. I think it makes the most sense to put the block reward after the transaction fees, since the block reward will always consist of uncolored coins (unless someone "pre-colors" them, which seems strange), and the convention is that uncolored coins go last.