Let's kick off a directed discussion about this. Please check out the general conversions thread if you need to see some example monsters and discussion on how to convert.
So, it starts with a brief investigation to track down the children. I'm not sure if it would be worth using the skill challenge mechanic for this (to help everyone get involved) or not. If not, Streetwise may be the key skill for this section.
Once at the house, there's an encounter with spiders. A _swarm_ of spiders coming out of someone is seriously twisted, as an aside. There's already stats for a level 4 lurker spider (175 xp each)... it might be reasonable to up it two of them. No idea how swarms work, but I'm sure there will be some reasonable solution or it'll be easy to make something up.
I'm guessing Jeva should be statted up to be a reasonable threat... if she adds in on some other combat, but not necessarily the badass threat she is on her own in 3rd. I'm guessing 'werewolf' turns you into an elite so she'd be, like... a level 2 elite, worth 250xp, or about half an encounter on her own.
The random encounters... can probably get reworked to just fit the new paradigm. Less of using all the same creature.
Starting into Level 1: Droskar's Crucible, I think it'd be cool to use the slaves' flight to trigger the gelatinous cube as it says in the sidebar. Probably worth deciding how difficult the kobold warriors should actually be. I'd be tempted to make the slaves minions and make at least a couple of the warriors real - like maybe mix them up a bit with 2 slingers, 2 skirmishers - could toss in a dragon shield. Or some totally new kobold variants.
Also, it may be worth looking deeper to see if there are any standalone traps and integrate them into some of the kobold encounters.
(Yes, not a ton of detail, more just brainstorming, but I'm just trying to prompt others to get started)