It turns out that I've been very silly and linked the download source for the modpack to its server file - so none of the client-side mods have been installing... I'm very sorry for not noticing sooner!
Installing a modpack using the Technic Launcher is easy. If you don't already have the launcher downloaded, visit our download page to get the latest version.
Type in the modpack name (Twelve) or paste the following url into the search box.
Finally, click Install at the bottom right of the launcher after you select Twelve from the list on the left. The launcher will handle everything else!
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