"I'm glad I could save it, but even though it made decent rollover and washing action , it cannot hold a candle to what the spiral ramp thing does. Especially with that Hotpoint 212 degree arc."
Sounds to me like you've been duped by another brochure! ;-) Seeing that spiral agitator at work in my machine with a full load, I could fully understand the less-than mediocre ratings bestowed upon it by CR. But enough bubble popping...
To make the filter work properly, you'll need the rest of the bits inside the agitator and there is a rubber gasket that goes into the tub. You have to remove the tub from the machine, or so I'm told. I have the complete agitator for the Fountain Filter but not the gasket.