For those who forgot, or just don't know, DMG2 had an entire chapter devoted to Skill Challenges. Let's see if it has any interesting tidbits and/or advice to help.
Introduction (pg 78)
They (skill challenges) should never replace the roleplaying, puzzling, and ingenuity that go into players’ approach to those situations, but they place that effort into a defined rules structure so you can more easily adjudicate them and players can more easily understand the options available to them.
Skills in a Challenge (pg 80)
A good skill challenge also allows for other actions outside the framework of the skill system to contribute to the party’s success. Spending money, using powers or action points, combat encounters, rituals, and the simple passage of time can contribute successes or do any of the things that secondary skill checks can accomplish.
Consequences (pg 80)
Whether characters succeed or fail at the skill challenge, the adventure must go on. Of course, there should be consequences for failing the challenge, but those consequences can’t bring the adventure to a halt. Penalties for failure in a skill challenge might include the loss of healing surges or some other lingering penalty, making a later encounter more difficult.
In addition to XP, characters might earn rewards specific to the challenge (which might simply boil down to the adventure continuing smoothly). They could also gain one or more treasure parcels, bonuses or advantages in future encounters, or information useful later in the campaign.
Ground Rules (pg 82-83)
Like combat encounters, skill challenges work best when you and the players want one to happen.
D&D is a game about creativity and imagination. If there’s only one specific, scripted path to success, you’ve lost what makes D&D fun. When you build a skill challenge, be prepared for it to head in a direction you didn’t anticipate or for the party to fail utterly. That way, the game moves on regardless of what happens with the challenge.
As in a combat encounter, if standing in one place and doing the same thing over and over again is the best plan, you need to go back to the drawing board.
A skill challenge is a lot more than a fancy extended skill check. The best ones embrace improvisation and a broad range of skills and abilities.
As in a combat encounter, a variety of options makes a skill challenge compelling.
It isn’t enough to pick a wide variety of skills. You need to create a broad range of subchallenges and obstacles within a challenge. A good skill challenge consists of a number of different incremental tasks that combine for a fun encounter. It isn’t enough to pull different skills into the challenge. The players should feel as though their characters have a lot of options and important decisions. Otherwise, a skill challenge turns into a boring series of die rolls.
Unlike a combat encounter, a skill challenge can cover hours or even days of progress.
Think about how long it should take the party to resolve the skill challenge. If your answer can be measured in minutes, you might be looking at a simple skill check. When you design a skill challenge to cover a day or a week of effort, you open it up to a wide variety of individual hurdles within the challenge as a whole and a broader range of skills.
Extending a skill challenge over a span of time has an important benefit: It lets you plausibly impose radical changes to the challenge without straining the players’ suspension of disbelief.
Each skill check in a challenge should accomplish one of the following goals:
- Introduce a new option that the PCs can pursue, a path to success they didn’t know existed.
- Change the situation, such as by sending the PCs to a new location, introducing a new NPC, or adding a complication.
- Grant the players a tangible consequence for the check’s success or failure (as appropriate), one that influences their subsequent decisions.
The characters should always be the active party in a skill challenge.
Placing characters in the active role has an important effect on your design, your presentation, and the players’ engagement. It forces the players to step up and make plans rather than sit back and react to your NPCs. It also compels you to create multiple paths and options. When the PCs are the passive group in a challenge, it’s too easy to allow logic to dictate that one repeated skill check is the best way to plow through the challenge.
And then the book goes more in depth over the next 5-1/2 pages, and continues to give various examples from pages 89-101.