I can't say anything about Altolamprologus, but I've had Julidoshromis and Multis in the same 60g before. They all ended up spawning. I had a fine, dark sand as a substrate, at least 3-4 shells per Multi, and about 15 cichlid stones from Underwater Galleries.
There was two main issues. The Multis had a habit of spitting the sand straight on the hole where the sponge on the tanks intake went into it, straight into the filter.The Julies bred a lot, and the fry were slow growing. The fry that where chased out of the rocks lived in the no man's land between the rocks and the shells, and any that got too close to the shells were killed by the Multis.
Make sure there's a wide area of bare sand between the rocks and shells. If you're very lucky, you might be able to find some Cryprichromis leptosoma, otherwise called a Sardine Cichlid, that's native to Tanganyika and lives in the water column. They're a mouth brooder. They're not common, and need to be in a large group. If you find any, make sure you don't get the Jumbo variety, a 60g of any dimension isn't big enough for the bioload.