Passenger side cabin leaks

Hello beautiful people.

I recently bought a '96 K11 1.3 GX and have discovered the sunroof leaks into the headliner.
I have removed the headliner and opened the sunroof, poured water into the catch tray and watched it leak out right where the rubber drain hose meets the collection funnel in the tray itself.

I sealed it with some caulk/mastic, solved the problem but it has started leaking again a few weeks later.

I also have the footwell leak which i have read up about on here and tried to find Pollyp's guide on fixing that but got to an "Oops that page can't be found".

Does anyone have a guide to repairing these? The car is too mint to just gaffer tape the sunroof :(

Many thanks.