DoctrineORMModule does not explicitly support autoloading without composer (since it's a mess).
As of current (0.7.*) version of DoctrineORMModule, the required packages are following:
What you can do is defining all the autoloading namespaces in init_autoloader.php in your skeleton application (explaining the mess). The code to replace is the part about the autoloader factory:
Zend\Loader\AutoloaderFactory::factory(array(
    'Zend\Loader\StandardAutoloader' => array(
        'autoregister_zf' => true,
        'namespaces' => array(
            'Doctrine\Common'   => __DIR__ . '/vendor/doctrine/common',
            'Doctrine\DBAL'     => __DIR__ . '/vendor/doctrine/dbal',
            'Symfony\Console'   => __DIR__ . '/vendor/symfony/console',
            'DoctrineModule'    => __DIR__ . '/vendor/doctrine/doctrine-module',
            'DoctrineORMModule' => __DIR__ . '/vendor/doctrine/doctrine-orm-module',
        ),
    ),
));
You will have to configure the various git submodules on your own
As of version 0.8.* of the modules, the dependencies will increase quite a bit because of how doctrine/common was splitted recently, so consider finding a solution to start using composer or you will just be delaying huge problems in future. 
This solution should work for now.