When a user has created a script, they can then enable it by right clicking on their object and choosing to enable. They can still access the DX properties of that object by holding down the ctrl key which will temporarily disable the script so that it can be manipulated (moved, resized, modified).

Windows comes with hundreds of COM objects already installed. One way to think of COM is as Microsoft's own "plugin" format for third parties to use. The advantage of having DesktopX able to use COM objects is that software developers can not only create potentially useful things with DesktopX but also help their software careers since knowing COM and .NET are skills heavily requested in the job market. This is a big advantage over learning some proprietary scripting or plugin format. Users interact with these COM objects using the scripting language of their choice (i.e. VBScript, Javascript or whatever other scripting language is installed).

There are some drawbacks, however. Unlike SDPlugins, COM objects are not easily distributable. For instance, if your DesktopX object makes use of the Microsoft Spreadsheet V10 COM object, then it may not work on someone else's system since you cannot guarantee that every system has Microsoft Office XP installed. So when using DXScript, this is something to be aware of if you plan to share your object with other users.

But obviously, if you know VBScript or JAVAScript, then DesktopX becomes a very powerful yet easy way to build custom applications and custom environments.

The advantages of using SDPlugin require some explanation. DesktopX objects are designed to be exported and shared with others. SDPlugin has been designed to be the same way. So if you use an object that relies on an SDPlugin and export it, that SDPlugin will be included as part of that object. Unlike the DXScript case where a user may not be able to use your object because they don't have a particular COM object on their system, an object that relies on an SDPlugin will work because the SDPlugin is part of the object. Of course, this also means that your objects will be slightly bigger since it has to include the .DLL file inside the object (.dxpack).

Another advantage of SDPlugin extensions is that they can directly call Win32 APIs. DXScript extensions can only use whatever is available in DXScript itself or in the methods available to any COM objects you access. SDPlugins are DLLs in themselves and hence can do anything that any other DLL can do.

As a developer, you'll have to pick which way works best for you. There is no "better" way involved. Each method solves a different set of problems.