Yes, I can confirm it works on SME6 - I used it twice today on different machines and can see no issues as yet.
It would be nice to see a pseudonym addition to it as well, but what it has is good. It ensures your import file has the correct syntax and doesn't break any system account rules before it starts the process - this is so much better than many other scripts that will start a lengthy process and THEN tell you "can't do" just as you walk away to get the coffee!
If you use the Groups option, you need to set those up first and subscribing to multi groups is not a problem.