Conan: Jeweled Thrones of the Earth consists of seven separate adventures, each a different part of Conan's world. To reflect how the Conan stories were written, the adventures encourage the reader to run the adventures back in forth in time, and, of course, like any roleplaying game, mix and match the adventures with other gamemaster ideas. Of course, the regular rules assume the adventurers have spent months carousing between adventures, so it's not difficult for the players to find themselves in one part of the world at one time, and another the next. Each adventure should take several gaming sessions.
Devils Under Green Stairs finds the players stumbling across the forgotten city-palace of Zukundu, where a trio of degenerate tribes have an uneasy peace that becomes bloody war. I would say that the adventure is intermediate in difficulty, with the gamemaster having to manage various intelligent (though vengeful) NPCs. The adventure is on the linear side, mostly assuming the adventurers follow a specific plotline in the adventure.
In the Pact of Xiabalba, the players set sail and are engulfed by a terrible storm from nowhere. They find themselves shipwrecked on a mysterious island, with the only survival leads inward as the party searches for water. There, they will hear the sounds of ever-distant war drums, meet soldiers with crests of a severed head, and a ship marooned in the middle of the forest. The adventure is linear, until a point when the players and game master can create their own epic struggle, leading to the climax of the story. The adventure has NPCs, including an experience sailor, haunted by events in his past, whom dramatic players may enjoy playing as PC's.
In Caves of the Dero, our heroes descend into supposedly abandoned mines to find more than reputed treasure. Tales of diabolic sorceries lead to a horrible creation. The adventure felt a little on the dungeoncrawly side, no surprise since Conan is an influence on generic fantasy adventures. This adventure serves as a good model of a "logical" dungeon lair.
The Ghost of Thunder River begins with a prologue where the players play Pict NPCs, who discover the horror behind the adventure. The next scene has the players as their own characters in an outpost woefully unable to cope with the rising attacks by the Picts. As the characters find out about captives taken by the Picts, they must decide between following the garrison commander's order to not help them, lead a rescue, or find the mysterious man now leading these different Pict tribes.
In The Thousand Eyes of Aumag-Bel, our heroes find themselves in a tavern after carousing, only to meet a group of armored men demanding, "Give us the amulet! Give it to us and Aumag-Bel shall let you live!" Aumag-Bel rules the city, and, assuming the PCs defeat the guards, soon find themselves on a chase through the market after losing their amulet to the thief-children, tracking them down to the Den of the Black Lotus. (If the PCs recover the amulet, a substitute sacrifice has been captured and the heroes must rescue her!) A downward tunnel from the den into the depths continues the twisted descent hinted at from the den.
"Will they die as slaves under the brutal summer sun, or break out and triumph, fleeing themselves from dreadful bondage?" The Red Pit starts our poor heroes as slaves in a mining pit, swinging into a revolt and escape. This pit escape is well-detailed and makes a fine epic battle, complete with mighty a'ghama beast. This adventure can be used in other game worlds, since it's not too Conan-specific.
In The Seethers in Darkness, the party has been hired by a scholar to find a lost city in the middle of a desert. A desert storm separates him from the party. Woeful to the heroes, the scholar is successful. This adventure is linear but doesn't feel like a railroad, as the players follow the scholar into the dark. This adventure is basically a series of planned encounters (almost a dungeoncrawl), but with quite a bit of Conan atmosphere. I highly recommend it over the Quickstart adventure.
The last chapter is Seeds of Glory. This chapter is advice for the gamemaster and players in creating -- or not creating -- a campaign for the gaming group. Different suggested outlines for campaigns are provided, as well as a suggestion that, since Conan's stories took place at different times during his life, so can adventure sessions. The chapter also mentions how Conan himself could appear, if desired, without overshadowing an adventure. Finally, the chapter ends with ten or so adventure seeds a gamemaster could develop.
I think the only concern I have about these adventures is, along with the core book adventure, that many of them involve the players pressing forward in dark passages, or encountering the climax of a ritual. Almost all of them have encounters with forbidden sorcery or lost civilizations. (Speaking of lost civilizations, maybe Modiphius could release a campaign where the party gradually learns about a lost civilization, instead of descending right into it.) Perhaps these adventures are better played a breaks between the more conventional generic fantasy adventures, much like the stories of Conan were in his life. Some adventures add fiddly little instructions a gamemaster is supposed to follow (eg. a series of die rolls to see how many enemies show up) that the gamemaster can ignore. I also recommend that the gamemaster run a few combats to familiarize himself with the enemies in the adventures and the game system. Most of them are human and intelligent, though pretty willing to put cause ahead of safety.
Finally, I usually recommend, for adventures, the PDF over book, including Conan: Jeweled Thrones of the Earth. You will only need one chapter at a game session, and can write in the margins for game notes. If you print out the PDF one-sided, you can cut out pictures and text as handouts to players. Some NPCs make fine player characters, and these can be made into handouts as well. Save yourself some money and lighten that load in your pack!