Thanks for the trip update! I thoroughly enjoyed reading about your problems, as I have been there, done that. Now you know why delivery skippers get the big bucks, as many times they are delivering boats which have been sitting around and have maintainence issues like yours.
Chances are your roller furling problems are caused either by the spare halyard getting caught in the furler near the masthead, or by the jib halyard wrapping around the forestay. See UK Furling Considerations
However, if the boat has been sitting around for a while, you should check that both the top and bottom swivels on the furler are not frozen.
Securing the main tack when reefing can be done by a line or a hook on the gooseneck, wich should go through a reinforced eye on the sail. If the stack of sail slides prevents you from using the hook, then use a simple lashing around the gooseneck as a temparary measure, and make up a webbing strop through each reefing eye with rings on each side for the hook as a permanent fix.
Your GPS speed should not jump around more than 0.1 knot. Read the manual and set the averaging to the longest setting if you can, and get a new GPS if you can't. If you haven't done it already, you will benefit from bringing a laptop withe the free downloads of Seaclear and the NOAA electronic charts of the area.
Get the engine running and the water inleakage fixed before you set out again, as the Delaware and Chesapeake are both notorious for light winds. Bring someone more experience with you, and plan on moving at night--its beautiful at night, but there is a lot of ship traffic and you need to know how to read running lights/charts/monitor CH 13 & 16 and predict where the commercial traffic is going, or you will have more adventures to write about. The AIS system, connected with a chartplotter or SeaClear, is really worth the $200 it costs around the bays and canal.
The biggest concern should be your wife. If she got yelled at while you were in crisis mode, you may be sailing the new boat alone.