Where a user is assigned as a course creator (but not globally) it can be problematic navigating to a category to click an "Add new course" button depending on the layout of the front page when logged in.
User assigned as CC globally: Add new course button is present at the bottom of any list of courses e.g. all courses.
Use assigned as CC in specific category(s): User must navigate to category where assigned as CC to access a "Add new course" button.
Change the rules for availability of the "Add new course" button and link so that the current setting that apply when a user is assigned as a CC globally so that they also apply when a user is assigned as a CC in one or more specific categories.
Alternatively, using the conditions above place an "Add new course" button on the front page of the site (when logged in) for every layout.
The ability to add a course to a category is still restricted by virtue of the category role assignments.
Users can select from permitted categories in the "Category" drop down in course settings.
Although there was some work done around this in 1.7, IIRC this proposal would take us closer to pre-roles behaviour without compromising roles assignments.
Point to note:
If course requests are enabled and the CC assignment is not global it is necessary for both buttons to be available to users who are eligible to request courses.