How does Scrumwise map users from the source control tool?
Scrumwise uses the email address to map a user. So, you should make sure that a user that you want to map from the source control tool to Scrumwise uses the same email address in the source control tool and Scrumwise.
If a user does a commit and Scrumwise cannot map the user to a Scrumwise user, Scrumwise will send an email about this to the email address that the user has in the source control tool.