Fane of the Drow works decently in the Crystalmists near Sterich or even in the Hellfurnaces as does Hellspike Prison.
I just got Fields of Ruin, and I think it fits rather well in Almor.
On the whole, the battlemaps are very usable for dozens of locations.
Not sure about the Hellspike prison maps yet.
I love me some battlemaps by the way. When running the fight with Brazzemal the red dragon from G3 I was able to use a dragon hoard map that came in Dragon magazine a few years back. Had piles of gold and bones strewn about. So much fun. Ok, not so much fun for the gnome cleric who got snatched by the dragon and spent a good bit of the fight in Brazz's mouth, but fun for me
I ran the Mushroom Cavern encounter as is for a group of five 9th level characters. It was a one-shot for a group of friends who were in town for the weekend. We had a lot of fun, the party was successful but barely so. Here is the character background I gave the player playing the dwarf fighter character just before the game session:
"Agnar Hringrim is a dwarven warrior from the Principality of Ulek. Ulek is currently engaged in a desperate struggle against the orc hordes of the Pomarj to the east. The war ebbs and flows but all that really seems to be accomplished is death. Far too many Ulek warriors have died in this stalemate. This war would be over if the elven Queen of Celene would send her armies to join in the struggle against the orcs. Instead the elves have closed their borders and called back their ambassadors. Only a few brave elves have defied their queen and joined the struggle against the orcs, but too few to turn the tide. Prince Olinstaad Corond has demanded something be done to force the orcs back across the Jewel River and into the Pomarj. The orcs have numbers and speed on their side. If only the dwarves had a way of quickly striking the orc supply lines and bridges, they could vanquish all the intruders on the Ulek side of the Jewel.
Perhaps something can be done about this. Ulek sages have uncovered a legend that may be helpful. The great traveler god, Fharlanghn is supposed to have walked every pathway on Oerth several times over. For a time his consort, the demi-goddess Erramu, accompanied him on his journeys. Fharlanghn is said to have broken her heart because he could never be persuaded to cease his endless wanderings and settle down with her. Erramu died of that broken heart. Supposedly, one of her eyes became crystallized and that if one holds it and calls out the name of a place, the Eye of Erramu will show the place in perfect detail.
Such an item would be of great use to the mages of Ulek. With it they could call forth the images of the bridges over the Jewel River and send strike teams there to cut the orcs' supply lines. Victory would be assured. The sages studied all the lore regarding the Eye of Erramu. Their best lead said that it had fallen into the hands of a foul mage known only as Vereorax.
Agnar has been commissioned by Prince Corond himself to pursue Vereorax and return with the Eye of Erramu. No other warriors could be spared so Agnar was given funds to buy mercenaries along the way. Following the best information and rumors he could uncover, Agnar headed northwest to the lower tip of the Yatil Mountains. Rumor has it that Vereorax is searching for the treasures of the witch Iggwilv in the Lost Caverns of Tsojcanth. If the Eye of Erramu can do what it is purported to do, then Vereorax may indeed find these treasures.
Agnar sought to recruit a team in the free and independent town of Highfolk. The town was gripped by fear and rumors that the witch Iggwilv walked Oerth once more. The people feared if her lost treasures in Tsojcanth were disturbed, Iggwilv would return and take out her wrath on the townsfolk. The Mayor of Highfolk Town, Tavin Ersteader has commissioned a band of adventurers and mercenaries to brave Tsojcanth and stop Vereorax before he can bring down Iggwilv's wrath upon them. Agnar has joined this band, but has kept to himself that he only desires the Eye of Erramu. Only the Eye matters, everything and everyone else is dispensable. The Principality of Ulek must be saved. Prince Corond has commanded it!"
I just bought "Fields of Ruin" last night so I haven't given a lot of thought as to where to put its encounters yet. I'll keep Old Almor in mind though. I agree that the "Fane of the Drow" encounters should go in the Hellfurnaces given the Drow history there. "Hellspike Prison" seems to thematically fit with the Hellfurnaces, but I've also been entertaining the notion that those encounters could be hidden within another level or two of "White Plume Mountain."
The next Fantastic Locations product is "Dragonsdown Grotto" due in July, correct? Should be fun to figure out where to put that in Greyhawk as well. Where does Tiamat wield special influence or enjoy cult activity?