The most important thing to understand when installing manually is that the version you create must have a consistent id. You must use the same id for every part of the installation process. In the example below we will use the id 1.6.4-LiteLoader1.6.4, if you choose a different id then you must alter this everywhere that the ID appears in order for the version to work.

installation steps

{
    "id": "1.6.4-LiteLoader1.6.4",
    "time": "2013-09-19T00:00:00-00:00",
    "releaseTime": "2013-09-19T00:00:00-00:00",
    "type": "release",
    "minecraftArguments": "--username ${auth_player_name} --session ${auth_session} --version ${version_name} --gameDir ${game_directory} --assetsDir ${game_assets} --tweakClass com.mumfrey.liteloader.launch.LiteLoaderTweaker",
    "libraries": [
        {
            "name": "com.mumfrey:liteloader:1.6.4",
            "url": "http://dl.liteloader.com/versions/"
        },
        {
            "name": "net.minecraft:launchwrapper:1.8"
        }
    ],
    "mainClass": "net.minecraft.launchwrapper.Launch",
    "minimumLauncherVersion": 16,
    "inheritsFrom": "1.6.4",
    "jar": "1.6.4"
}