FIRST) NEVER use numbers in Category- or Course names, because you will be changing them all the time which means unnecessary extra work. Use more neutral names that are likely to never change. One of my Moodle-Admins did this at a University-Level, not knowing, that I had stopped this already in 2004/2005 and so he began renaming, copying and moving around a lot of courses at every start of a new semester. Of course he thought to archive old courses this way, but this was not only wasting time to copy and move around, this meant also wasting a lot of space on the data-disk, because doubling a course means to have FOUR times the data, twice as course and twice as a backup-zip-file. So stop this before starting it. If you need an archiving strategy, choose one which is optimized. e.g. copying only the backup-zip-files to a separata archiving-data-disk or letting the teachers download the needed zip-files directly, so as not to bother you, etc.
SECOND) For programming/automation reasons you need fixed names so that you can change my Translation-Table for categories directly in my code. I have TWO Translation tables set up, so that I can switch the table to be used, depending on the server on which I create the courses. This means I have to use one table to translate the same category mentioned in the import file to use on the production server and one to use if I test the import on my test-server, where the same categories have different Moodle-IDs from the production server.
THIRD) Be sure to never import such things directly on your production server because you could mess up your Moodle-Database. Do a first run and all tests on a test-server first. Even after 3 years I continue to test the whole import on the test-server first. And if everything works fine, I repeat the import on the production server. My actual version 05 on which I am working at present, is optimized for our environment and will be starting to run as cron job, so that our teachers can compose Moodle course orders directly in a web-interface showing them all the courses registred in our School Administration System (where you have also the Teachers, the Students, the courses they should attend, their grades, etc. etc.) So this cron job will run once a day and create the desired courses on Moodle. In other words, I have interfaced our School Administration System with Moodle simply by exporting what I need to know out to a cvs file. Then I import it to Moodle.
Of course, if you provide the correct Moodle category IDs in your import file, then you can switch off my translation tables directly in the code.