We first addressed the key risk points.
The development process:
We upgraded the clients' development processes to match the task at hand. We knew we'd need controlled iterations and review processes around the release; we instilled them and introduced the design team to them. For example, email previously had served as the medium for all project management including initial scoping and requirements, delivery of artifacts, management and task tracking and bug reporting. This had worked for projects of a smaller design-oriented nature, but would not scale to the new project. We included both the design team and Coca Cola IT in our web-based task tracker, to more rapidly report, triage, and resolve bugs and issues. We consolidated their specification documents in a version control system.
We introduced shared FTP, staging environments and continuous integration to the clients. We initiated multiple test runs of the app as new components were added. Although the Coca Cola team themselves had originally been worried about whether the project could even be completed, in the end we delivered smoothly, on time, without any hiccups in deployment.