Project creation can go wrong when the Project Manager is configured to be set from a template.
Create an attribute category.
Add attributes to the category.
Assign this attribute category to a Project template.
Assign a Project Manager to the template (PM1 for example).
Set the option "Set Project Manager" off.
Login as PM2 and create a project based on this template.
PM2 will become the Project Manager.
In case the Project Requestor is not the same as the Project Manager of the template, Project Requestor will be able to create a project but s/he will get the error that s/he doesn't have permission to perform this action: "This user doesn't have the rights to manage this role" and roles won't be assigned.