API support in Windows Live Spaces is not enabled by default, you'll have to enable it by enabling email publish feature in the Live Spaces setting page and set a security code for it.
To add Windows Live Spaces to BlogSync:
Please notice that Windows Live Spaces only allow application to read 20 articles through the API, so if you are trying to copy contents from Live Spaces to other blogs, you'll have to find a way to backup your articles to RSS feed format and then using the RSS read functionality to copy them to another blog.