By default, Dorico does not use the USB-eLicenser. By default, it uses the Soft-eLicenser. This means that you do not have to connect the USB-eLicenser at all. If you buy the download version of Dorico, you will not even receive a USB-eLicenser: that will only be included with the boxed version.
You only need the USB-eLicenser if you need to run Dorico on more than one computer. You then transfer your license to the USB-eLicenser, and if you want to continue running Dorico on more than one computer, you leave the license there, in which case, yes, the USB-eLicenser needs to be connected for the entire time the application is running, not just at start-up.
If you want to transfer the license from one computer to another more permanently, you only need the USB-eLicenser as the temporary repository for the license: you transfer it from one computer to the USB-eLicenser, then plug that USB-eLicenser into another computer, and then transfer it back from the USB-eLicenser to that computer. Thereafter you no longer require the USB-eLicenser on that computer.
It’s worth pointing out that the transfer of a license from a USB-eLicenser back to becoming a Soft-eLicenser is not currently possible, but it is anticipated that it will be possible by the time of Dorico’s release, or shortly thereafter.
It’s a little bit of both. The Soft-eLicenser from a technical perspective does only allow activation on a single computer, and there is no current capability to allow more than one computer for a single activation code. We considered supplying more than one activation code with each Dorico license, but this opens up the possibilities for unscrupulous people to share or resell their second activation code, which may seem far-fetched but in fact happens all the time (compare, for example, the large secondary market in Steam keys in the PC/Mac gaming market). The solution our management have decided upon is the best balance available between our business needs and our customer needs, based on the current capabilities of our licensing technology – with the emphasis on the words “current capabilities.”