The issue with the failure of the export/import was due to some pages that had been approved/published had a parent that had not been approved/published. So much for asking the rest of the team to ensure all content was ready for the deployment.
On another issue we have a number of custom groups that are used where we have broken inheritance on reuseable content and image libraries so that the end users cannot delete or edit these. When the deployment is run to the WFE these custom groups are not exported, the deployment runs but warns that groups could not be imported. No matter which options you select in the deployment process nothing happens. You will not notice this if the default groups are only used.
As a work round we have backed up and restored the site to the staging and production servers and users will edit content from there and the deployment will be to WFE's and anonymous access turned on so it will not matter. But it is a gotcha!