I cleared all the cache and data in the first place... didn't work then, because survey-smiles didn't show up at all in the list.
completely uninstalled Firefox a few days ago, while doing all the other methods.
Yesterday went through thr site list again, after using all the other avast tools. Alert still coming up.
Checkd the data list and there it was.
best I can guess is that the cookie attached to something else the first instance; and then droped in as Survey-smiles after the reinstall.

?
It's only been 24 hrs so let's see what happens.
I have never visited survey- smiles, so it's come in on something else?
Cheers.