Connection UiPath - Appian.. Help!

we have read all the forum posts on the topic and followed the guide for connecting UiPath and Appian but we have 2 problems:
1 - we can’t figure out what values to enter in the Appian connection panel (we always have “Invalid credentials, failed to login” - see the image). Does anyone know what do we have to insert to enable a Connected System for UiPath with UiPath Cloud?
2 - when we try to use “Start Human Activity” inside “Appian scope”, we have this error message: “An error occured while trying to connect to Appian. The user does not have the necessary credentials.”
Thank you,