I created a first version of a Visual Studio project that are meant to be used as a easy way to add functionality to an Umbraco installation with no need to have access to the web server file system as the files are packaged into a … package. This first version includes a sample XSLT extension class and a sample Web User Control.
To begin adding your own .net-functionality to an existing Umbraco site you just need to
1) download and open up the sample project in Visual studio 2008
2) add your own code to it (using umbraco core classes if you like)
3) build it, it creates a package zip automatically
4) install it as a local package into your Umbraco site. Then you have your own functions ready to use in the Umbraco Xslt Editor.
No rocket science, just a VS project with some Umbraco binaries, sample XSLT Extension-class, a package folder and package file used for package creation, some build rows and a zipper.
Download the first beta from here http://www.bit.ly/979WOV