I am trying to cock the ballista in the very beginning of the game, but keep getting interrupted by attacks. How many waves of fighters do I have to kill off before I can cock the ballista? Or have I missed something along the way?

Kill some guys, cock Ballista, kill some fighters, aim, kill some fighters, shoot.

Notice, you need to click very fast to get the yellow bar all the way full. If you don't get the bar full you will have to repeat infinitely.

I was able to get the ballista cocked. Do I need to use the same clicking frenzy to aim it? Do I need to manually aim it or will it let me know when I am in the right spot?

Thanks for your help.

To aim you need to do another 'clicking frenzy'. After that you get another bunch of hostiles, then you can fire it. Do not forget to look up the assassin in white in that place (minor spoiler) since it will give you an ability.

Sounds about right :( The "aiming" QTE is very tightly timed, and you have to go at it ridiculously fast. To me, it's the most infuriating QTE in the game.

Don't forget you can also turn off "Difficult QTEs" in the options. It should help make the bar easier to fill, and you can always turn the option on again afterwards.

yeah i totally did :(

Well, I guess I won't be playing Witcher 2. I am clicking as fast as I can and still don't get close to the end. I turned off difficult QTEs and I even turned the game difficulty to 'Easy' and nothing works. I don't guess it gets any easier the more times you do it either.

It's a shame they put such a hard trial in the beginning of the game, especially for us older gamers.

Thanks for your help, guys.

I had no difficulty with it. It seems being 'rythmic' about the clicks helps. I have no problem getting you past this if it blocks you, send me a private and I provide the email address. Someone helped me on the Kayran quest in a similar way, the game is quite unbalanced but it is worth playing it out even with the quirks it has.

You'd have to be 90 or suffer from arthritis to struggle with this.

I'm 47, and I had no problems with any part of the game.

OP: Technically this was solved, though a bit less satisfactorily than we'd all probably like. Still, mark the appropriate "solution" post as "solved" :)

Not sure if this helps, but consider temporarily lowering your resolution (on the Configurator/Video Configuration). Maybe your system is not registering the clicks fast enough?

I have been trying to fire the Ballista at the barricade for a couple of days. I see that other players have had trouble loading and aiming the ballista. I have loaded it and aimed it but not been able to fire it.
I have fought off 5-6 swarms of foes without getting a "fire" button. Waht is the problem with not being able to fire the damn thing?
Can I go back to some point and not get this quest? If so , where?
This subquest is annoying. but I love the game so far.I just want to get beyond this point.
Thanks for the help,

This quest is necessary to progress in the main storyline, there's no option to skip it.
As for your problem, are you sure that you killed all enemies in the area (some of them might be hiding behind the palisade).
If the advice doesn't help, you can contact via chat and send me your savefile and I'll try to find a solution.