This scenario was hell, literally.
The skill challenges were fairly stiff, and didn't make much sense considering the evidence we had in hand. We did some roleplaying but thankfully had the skill set to make all the talking a formality.
The map was gargantuan, our GM had it printed out on a poster sized map and the scale was still too small to use as a combat board. I'm sitting there looking at it thinking "when the crap hits the fan and we have to fight our way through a fortess full of Hellknights, this is either going to be awesome, or suck the most suck that anything has ever sucked. Then there was no giant fight with the Hellknights. As Harry Potter would say, "Letdownius Majorus".
Now to my real beef with this session, whomever thought the dimensional anchor effect in the second fight was a good idea needs to really consider what that means.
Sure we found some potions, but as the DM pointed out, they only have a 40% chance of working each. One party member was still cursed and my mount (as a cavalier) was cursed after we had downed them all. What now?
What now means that 2 of the 5 party members are not heading through the portal, it would have been suicide for my gnome cavalier if he was mountless and had gone in, and your armored jello dog that was designed by an angry 12 year old is going to slaughter those 3 other PCs without breaking a sweat. At this point the adventure was over, sorry Zartra, poor dice rolls mean you rot in hell.
Luckily for us, we players came up with the idea that the Hellknights must have a chapel and some clerics who could possibly remove the curse. The GM used a handwave to say that we slipped over there unoticed and that they were prepared to remove our curses at standard spellcasting costs and chances of success. It still took almost a 1000 gold between the 2 characters to get the curses removed. So yeah, thanks a ton for that.
I want to point that out again, if the GM hadn't handwaved a way for us to get uncursed, 3 players would have stepped through the portal and 3 players would have died a certain death. Was that the goal behind the design of that mechanic? If so, good job.
You shouldn't paint characters into a corner that keeps them from continuing the mission, plan on giving them a way around whatever happens, or else that's just poor game design. If you only mean for the curse to prevent people from using dimensional travel during the prison fight, have the potions they find have a hightened caster level for auto success, or better yet, don't force them to rely on dimensional travel to complete the mission!!!!!
One last thing, her "boon" at the end of the scenario is utter garbage. The only thing you've done is split my level appropriate reward down into two chunks, one of which I have no use for. At this level I already have all my magic items of 3000 gp or less, my handy haversack, my +1 armor and weapons, and the other cheap wonderous items I had slated for purchase. If you had written it as a one time 10% discount on one item up to the value of the GP received for this scenario, I think that would have been a nicer idea. Instead I'm forced to buy something for 3000 gp I don't need and sell it for half price, effectively cutting my reward down even further after having to pay extra to get my mount uncursed.
Boo.