Not sure what you mean by offline/online but you may want to know that the program offers the web access feature. This will make the main installation of Inventoria to act like a server, so other users can access the data over the internet from other devices. If you want to know how to set it up, you may want to watch this video tutorial: https://www.youtube.com/watch?v=Zmv2CdYVJz40
The license can be used on one single computer at a time. You should be able to transfer it to a different machine as long as it does not continue to run on the old one.