Yes, you can. Again, please note that each key has a maximum number of uses/updates assigned to it. See the previous FAQ item.

A key expires either if the expiration date or the maximum number of uses for that key has been reached. One use is counted when you update to the latest version/build ComfortUpdate.

Yes, LimeSurvey software is free open source – everyone can use, modify and distribute it for commercial, private and educational purposes under the GPL license v3(exception: the name and logo LimeSurvey is trademarked, so please don't advertise commercial services using the LimeSurvey brand.)However, the development of LimeSurvey needs to be on a professional level, so we need funding to pay our developers.That is why we offer a ComfortUpdate package for LimeSurvey, which can be used to conveniently update LimeSurvey from within the application. If you don't want to use the ComfortUpdate function, you can still update to the latest version manually.