When I stumbled back into gaming some years ago, I was recommended the Pathfinder Beginner Box set as a good choice to reenter the world of funny shaped dice.
While the experiment of PF didn't really work out for me, and I eventually rediscovered the Old Ways of Gaming (tm), I did appreciate the product of the Beginner set. Having picked up a number of introductory sets and quickstarts (and of course holding fond memories of my old Holmes box set), I think that Paizo put together a good product. It does seem to be inspired by the Red Box and similar sets of yore, with separate, slim player and GM manuals, an intro adventure, and a number of accessories (char sheets, map, stand-up minis, etc.). The material, and a few free supplements available at the time, provided sufficient material to roll up characters, and get the character choices to 3rd level.
The GM manual includes a 10-room dungeon, "Black Fang's Dungeon" as an introductory adventure. Like the intro adventure in the B/X books, the scenario is interspersed with how-to's on running encounters, skill checks, combat and other nuts and bolts for a beginning GM. And it has a dragon.
So why not convert it back to OSE-B/X? I was curious on how it would fit, if I could do a direct porting over. Plus I wanted to experiment with the terse presentation style of the OSE adventures, such as "Hole in the Oak", etc.
So how does it look? Well, the original scenario is a bit encounter-heavy from an old-school design style. In ten rooms, I count six encounters (one can be negotiation, and a second negated with an application of Cleric). The remaining rooms are one empty, one trap, and two special, if we are using the classic "room content" matrix.
Six rooms contain recoverable treasure, at least two of which will be important for confronting Black Fang. From a B/X or similar "Treasure Type" determination, the value and types of treasure actually roll over fairly directly. I really only tweaked one bit of treasure (a scroll) in my interpretation. (Edit: I also multiplied Black Fang's gp total by 10 to sit more in line with B/X equivalents)
For the monsters, most are basic underground denizens (goblins, skeletons, spider). I converted a Pathfinder aquatic critter to a roughly-equivalent giant frog. Black Fang is a low-HD "juvenile" black dragon, with some adjustments to AC and damage proportional to the reduced HD (although still plenty deadly to some low-level mooks). In general, though, I think it fits pretty well across the two editions, although YMMV.
Anyway, here's the Experiment. All pared down to four pages (no spiffy art, layout, or advice).
And the Original for comparison.
(Heh, forgot that a B/X party could still drop a nuke on Black Fang via sleep, if someone held the spell in reserve. Better turn in my old gamer card.)