I'd suggest filing a support case here. I don't see anything wrong with the call and I can't reproduce the error with that same call to my own instance.
Smart lists currently can't be extracted via the API. You can use either Get Leads by Filter Type or Get Leads by List ID to extract them from a static list.
Sorry, no, I just need the raw request and response from your call. I don't need your access token or munchkin id. I suggest you edit your post to remove both of those. Thanks.