Well, I think this is actually a legit rate limiting issue. Since, as far as I can tell, Instagram no longer offers capability of XAuth (using a username and password), I cobbled together some patches to the current release of Instapress to make it work with a registered API client on Instagram.com
– provide a redirect_uri to add to your Instagram “client”
– provide input for client_id and client_secret
– step through the OAuth process to retrieve a token
I have it working and will submit to the author for review … unsure if it needs additional work, but i will submit patches to the forum shortly if anyone is desparate and needs something now