When it Crash by the first start, Test it again, it should work then.
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 (Avalon47774) or paste the following url into the search box.
Finally, click Install at the bottom right of the launcher after you select Avalon47774 from the list on the left. The launcher will handle everything else!
When it Crash by the first start, Test it again, it should work then.