How to add a collaborator during modelling phase

To add collaborator in a template during the contract modelling phase select the Collaboration Tab.

Here you can search a member to add. The member can be part of your team or an external member, who you can invite.

When you add a new member in the template you can also assign him a role. 

If
he is an external member he cannot have a manager role, but if the member is part of your team you can select him as a manager in the template.

You can also edit the role during the modelling process and remove the member.