Hi Harvey,
The 'watch-head' was only built in the original CT's of the type IX boats. CT's of the type VII were too small and did not have this luxury feature. It was on stb side of the solid bulwark part of the CT in sort of a hinged pull-down box (similar to the pull-down wash basin in an oldfashioned pullman type sleeper). Effluents drained down a pipe inside the CT skin, under the weather deck and out one of the drain scuttles a little above the surfaced W/L.
It was used in fair and foul weather by the watchkeepers.
Torp transfer was complicated and done only in the calmest weather. In short a collapsible derrick was rigged on both the supplying and receiving boat. With the help of these derricks and the windlass the eel was transferred to and from lashed together inflatables paddled alongside the boats. Rgds, RB