How can we create a user group that would allow users read-only access to the project files?
Harvest Software Change Manager all versions
Create a user group, or use the one already created, and assign your read-only users to that group. Then, that user group will be added to the Execute Access list for the Check Out for Browse processes across the various projects of interest. Ensure this user group is not assigned any other Execute Access permissions. To get a listing of all access permissions assigned to a specific user group use the query in this article: Finding all access permissions for a user group
More information on access permissions can be found here: Control Object Access