Now that the hardest part of creating the Custom Partition is done, package the CP for UMS. You are already familiar with most of the steps from earlier in this tutorial.
Upload the *.inf Metadata File to UMS as a new File.
Create a Profile for the CP with the Initializing Action set to: /custom/chromium-browser/custompart-chromium-browser init and the Finalizing Action set to: /custom/chromium-browser/custompart-chromium-browser stop
Create a Custom Application with the Command set to: /custom/chromium-browser/usr/lib/chromium-browser/chromium-browser
Assign the CP to a new thin client in order to test everything.