Following these instructions: https://developers.google.com/google-apps/extensions-console/
I am unable to deploy an in-house Contextual Gadget to a Google Apps Domain.
Creating, assigning Manifest/Extractor(including validation) and deploying appear to work fine, however Granting Access results in a 302 (redirect) to the Google Apps Admin Console and the Gadget does not show up in the Marketplace Apps Management console.
UPDATE - Developed a workaround
1) Follow instructions https://developers.google.com/google-apps/extensions-console/
2) Then go to https://console.developers.google.com/project and select your project
3) APIS & OAUTH -> Credentials -> Create new ClientID
4) Select “Service account” then “Create Client ID”
5) The private key is not necessary for this process and can be discarded. Press “Okay, got it” button.
6) Go back to the Marketplace Apps console: https://admin.google.com/AdminHome#AppsList:serviceType=MARKETPLACE and select your project
7) Select “Data access”, then “Grant Data Access”
The Contextual Gadget should now be deployed and have the correct permissions