1. A software system development apparatus hosted by a host organization, comprising: a processor; a computer-readable medium operatively coupled to the processor; a system design tool program stored on the computer-readable medium that, when executed by the processor, is operable to: grant access to user computers inside and outside the host organization, wherein the user computers are remote from the software system development apparatus; store, in accordance with the Reusable Asset Specification (RAS), a collection of reusable software components in a catalog in the system design tool program; generate, in response to commands from one of the user computers, a real-time embedded control software system by selecting one or more software components from the collection of reusable software components stored in the catalog, as well as from one or more collections of reusable software components stored in accordance with RAS outside the host organization, the real-time embedded control software system being generated on the processor of the host organization without any software components being downloaded to the user computers from the host organization; and regulate user access to at least one aspect of the system design tool program according to one or more authorization categories of users of the system design tool program.