Mast: Reefing Lines and Tackle...
OK, what I do with the reefing lines at the boom end is to wrap them on top of the flaked sail and then tie them with a sail tie before covering. Before raising the sail, I just let them hang, but watch to be sure they don't snag on anything. Usually, if I toss the slack on top of the dodger, they wont. At the mast, I just pick up the slack, coil it and hang it on a cleat, alto I could just as easily toss it over the sail.
As far as the two-part tackle for the main sheet halyard, it's really simple. Attach a low-friction lightweight block to the mainsail headboard where you now shackle, and lead the (new longer) halyard through that block and back up the mast to dead-end at the mast crane. It's common on cats; there is one just down from me with the rig, but I won't be at the boat for a week or two to take a photo.