Many Mk11 owners have written about how the companion way cover drains right onto your seats when it rains. I decided to fix it this year and caulk around the seam. I also have been trying to drill out and fill every deck fitting with epoxy to prevent water damage in the event a fastener leaks. When I removed the cover to drill and fill the holes I found the screws had been leaking and caused significant damage to the core material in the cover. Thankfully it's and easy fix and you won't see the repair because it on the bottom of the cover. I have done about half the fittings on the boat over the last couple of years, but after seeing this damage and realizing how lucky I was it was an easy fix I will spend the next coupe of weeks doing every remaining deck fitting. My rough math says I have just over 75 holes left to fill. I have done about half already. Its amazing how many fastens are in your deck. I did the enclosure snaps yesterday, that was over 30 holes.
The rotten care was dug out and replaced with plywood and epoxy and a couple layers of fiberglass. fortunately the repair ins not visible and easy to do. The cover was replaces, all holes in the cover and deck were cored with epoxy and the joint around the cover was caked to prevent water from draining down the channel.