Hi again asqui,
Re your grind settings..... this will depend on a few things, namley:-
Whether you are using the Single or Double Basket in the PF, and
The type, degree of roast and freshness of the Coffee Beans you are grinding, and
The Tamping Force you ar using, and
The ambient conditions at the time you are pulling a shot, and the list goes on.... :-?
When you are just starting off with a new machine though, its probably the best idea to use and stick with the Double Basket until such time as you can confidently pull consistently good shots. I had a Lux when I first got my Mokita and I think from memory, I used to grind on a setting just below 5 to achieve acceptable shots with a Double Basket and coffee only 2-3 days out from roasting.
Of course, this all depends on your having the coffee dosing on the money, the coffee evenly distributed with no voids and the tamping action down really consistent. It sounds like a lot of mucking around but once it all comes together, you can pull some exceptionally fine espressos.
Anyway, Id start using the Double Basket on a grind setting of 5, pull your shot and see what happens. If its too quick, adjust the grind one step finer until such time as you are getting a 60ml shot in around 25-28 seconds. Once you can do this reliably and consistently, you will be 90% of the way there 8-).
All the best asqui and happy brewing,