In C#, if you want to create a Word document you can use the OpenXML SDK from Microsoft. With that library you have full control of what you do, however, if you are new to the library, you may not like it. To generate a simple document you may want something more practical, like the HTML to OpenXML library.
I created an example Visual Studio 2012 Project (OpenXML SDK 2.5 dependency downloaded automatically via NuGet) in ASP.NET 4.0 that demonstrates how easy it is, thanks to this library, to generate a document. You can save a file on the server or stream it to the user. My example includes both cases.
Update 2013.07.29: added patch for umbraco 6.1.2 to 6.1.3.
If you, like me, like to upgrade umbraco by overwriting only the changed files (instead of the entire umbraco, umbraco_client, bin directories) as recommended in the umbraco general upgrade guide, here a collection of patches (zips containing only the changed files) that may be useful to you.
I created them by checking the differences between the old and new version.
I used Beyond compare, a commercial program that works really well for me. A free alternative can be, e.g. WinMerge
If you installed some packages that may have changed your config files, or even your language files, proceed with caution and check the differences with a comparison tool as I do.
So here the patches. Use them on your own risk! Read the readme.txt in the zip files for more details (such e.g. files that have been removed and you can delete as well).
So you want an easy upgrade patch for version 4.11.x to version 6.0.0 (I just tested it from 4.11.1, but it should be ok also for 4.11, 4.11.2.x and 4.11.3.x)? You can follow the umbraco guide, download the new zip and overwrite the bin, umbraco, umbraco_client folders and merge the config files as explained, or prepare your own patch, or you can also use my patch here: umbraco-upgrade-4.11.0-to-6.0.0.zip
Please be careful: merge the config files and web.config with a tool like Winmerge. I use a commercial tool: Beyond Compare 3, which is one of my favorite programs and I can only recommend it, it costs only 30 USD. If you deploy many patches or you need a really good comparison tool, this is the one to use.