We recently changed the way that Assembler network licenses are shared out to make it easier for many users to share a single license. Previously an Assembler license was checked out whenever you loaded MacVector with Assembler. However, now an Assembler license is only checked out when you start a new assembly project or open an assembly project. Thus leaving it free for one of your fellow users if they need Assembler. This means that a license can now be shared a lot easier than before.
Contact MacVector Sales if you are interested in adding Assembler to your license