The new version of the connector is using a different type of authentication for the REST and you will need to request different access keys than the SOAP version used. While we're finalizing the release, you can create a new Criteo REST API client at: https://marketing.criteo.com
This is a fairly huge update, so please report any possible problems by submitting a Support Request. Also, when interpreting results, please consider that the connector is in Beta stage and will be for still some time. We're doing our best to keep existing queries working, but the new version has lots of field changes. This might affect what kind of reports you'll be able to create.
The updated field list can be found under https://supermetrics.com/api/getFields?ds=CRI.