The first Forgotten Realms adventure from Dungeon is a very short adventure that is aimed for Level 2 characters. The adventure is set in the Gray Vale so if you had placed your PCs in Loudwater from the first adventure in the FRCG. This makes a good continuation is much more logical continuation than, say, the Scepter Tower of Spellgard.
The adventure synopsis is that an unnatural winter, months early, has fallen aroud the Gray Vale region and it is affecting the crops of Loudwater. The leaders and wise ones of the town suspects that it is the working of a Dwarven Warlock named Draigdurroch who lives in a tower he build 30 years ago, a mile away from the Dire Wood.
So the PCs are hired/urged to head over the tower, find the souce of the winter and stop it once and for all.
The thematic monsters like the frost goblins really goes to show how easy it is to take existing monsters and slap a theme on them which shows through the crunch.
The other interesting I found about the adventure is the Skill Challenge to weather a blizzard storm.
Like I said, it's a very short adventure. It's quite a standard crash down the door dungeon which only has 3 levels. It's a great hack and slash adventure so expect combat to be aplenty for this one. If it wasn't for the combat, this could probably be finished in a session or two of 4 hour gaming. Combat is going to drag this one out so maybe spacing the encounter between each session is probably a good time
My only concern about this adventure is once the fighting starts, I don't think the PCs are going to be able to find enough space or time to get a breather and replenish their resources. But this is probably one of those dungeon where the players only have to visit once.
In terms of leaving plot holes/hooks, this adventure leaves quite alot of open space for opportunities. First, where is the warlock? It says that he is trapped in the Feywild but what if he manages to escape and find the state of his tower (and research?)?
Or, maybe you can introduce Draigdurroch's partners in crime, a cabal of warlocks that haven't made an appearance yet suggest the potential of something far more sinister.
Then, there is the Fey. How would they feel having their seal on a dangerous warlock broken by some intrepid adventurers who claim they are doing the right thing.
This adventure is also probably a good spot to drop off little hooks and questions for PCs whihc gives them a motivation to travel to find Lady Shararel from the Scepter Tower which is what the adventures suggest.
Overall, this feels like a sidetrek adventure which is bound to lead the PCs to larger adventures to come.
I hope they would continue with the series (even though I won't get to see them in the future) but it's nice to see that the Realms is going to be supported further with more adventures other than Scepter Tower.