@pullman Strange... The need for an ad-blocker shouldn't even be necessary, as foxPEP blocks most ads / trackers out of the box, just by itself resulting in accelerated site loading.
I believe the inability to log in to Firefox is normal across the TFF codebase, for some kind of reason. I recall getting the same behavior even on a vanilla Intel TFF install.
You did not ask me the following questions, but I will chime in to say that for all I've used of it, I am of the opinion that BluHell is nearly useless and the last time I tried it (which was, granted, some while ago so I may not have the greatest accuracy) did not block anything.
uMatrix is necessary if you seek to block every last thing from loading that isn't essential to the web page itself, which can still offer an additional speed boost on top of foxPEP, but I'd like to think that foxPEP in its current iteration carries the brunt of the performance gain from its built-in adblocker without the (admittedly minimal) addon overhead. It seems to have served its purpose nicely thus far, and is holding up quite well in that regard.
foxPEP's engines are, in essence, there for organization and effect prioritization. What you see contained in the More folder are the individual engines split into their own independent preference file, with the main preference file in the parent folder being a combined version of all of them (which is what the user is supposed to use). They are useful as separate files primarily for debugging purposes and effect-gauging.
In any case, AquaTrimcelerator / AuroraTrimcelerator (depending on the OS) can also make a big difference in fine-tuning the system for increased performance by reducing the overhead, which has been confirmed to result in even faster browsing. You may give one of them a look if you have not already done so.
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