To setup an Autotask API user for Mindmatrix integration, you will want to account for the following settings. 

Within Autotask go to ->Admin option -> Features and settings

Under Resources / Users (HR) selection: select security levels option

Edit the role, or create a new role for this API User.

The following permissions are required to allow the sync to function properly. 

1. General Information section The Security level should be set to "active"

2. CRM section select "Full" Permission: It should have the object permissions for Account, Opportunities and To-Do's under CRM section. 

3. Admin section: will require the below choices. 

 4. Other section: will require the below choices. 

5. Apply Security level to user

You can assign the role to the user, by editing the user and selecting the security level.