To upgrade the Developer client, have each author run the setup program on the appropriate computers to install the client. Make sure you install the new version of the Developer client in a new location that is different than the previous version.
When you launch the upgraded client for the first time, the behavior differs depending on the version from which you upgraded. If you are prompted to convert the existing profile, do so. If you are not prompted to convert your profile, you must create a new one.
You must have administrator privileges to the computer or at least have necessary permissions set to upgrade the software.
Note: You will experience errors if you try to connect an upgraded Developer client to a server that has not been upgraded. The server should always be upgraded first.