Strut Questions

[Al S]

Car-  Audi 1990 80 2WD

I did my struts the other day and now I have some questions.
I replaced the strut cartridges, springs, bumpers, strut mounting bearing, castle nut, stop and top nut.
The strut mount bearing is a high density unit from 034 Motorsports. 

I put everything together, tightened the castle nut, placed the strut assembly on the wheel bearing housing and snug up against the underside of the top of the fender. I placed the stop and tightened the nut down tight. 

Now a week has passed and I can hear the right strut moving around, something is loose. With the wheel on the ground, I took the top nut off and removed the stop. The castle nut was loose.  I tightened it again, down hard. Shoved the strut assembly up against the inside of the fender, little rubber rim from the bearing up into the hole. I placed the stop and tightened the nut back down.

Question: When I turn the steering wheel the upper part of the mount, inside the engine compartment, rotates. I thought the bearing should keep the mount from turning. The green side of the bearing mount is down and against the spring cap. Is that normal.

Seems to me that if the bearing mount turns, it will wear against the fender and loosen itself up.

What is wrong here?

Thanks for the help.

Al