Here is the link to the adapter that I used. I have also started using a metal flexible hose. So far it works fine. I just disconnect it and drain when it's freezing out.
I am working on a mod for shower curtain, so far I have a hula hoop to hang the curtain from and plan to attach it to the ladder. Have not decided on what to use to attach it yet, as I would want it to be easy to remove if I move the trailer. I live in mine so it won't move until I find a permanent place to move it too, but I may go camping sometime. Any way just wanted to mention the hula hoop in case you decide to do yours. I think it is perfect and cheap and comes in a variaty of sizes to fit your need.
The last time we were camping my DW ask me to please go take a shower with the outside shower,,because if I did it would scare all of the mosquitoes to death then we could enjoy sitting outside the camper…