If you have any problems installing the patch or find that you still see compilation issues after you install it, you'll want to contact Microsoft product support for assistance and they'll help debug it further.  Calls to Microsoft Product Support are free if they are related to a product bug (either a QFE HotFix request or a product bug you are running into).  You can find details on how to contact Microsoft product support on this page (it allows you to lookup the local phone number to use by country).

Most versions of Visual Studio also come with free product support tickets (for example: VS Pro with MSDN Premium comes with 4 support tickets per subscription).  You can use these support tickets for getting help using .NET or Visual Studio (for example: to get help chasing down a bug or performance problem in your own code, or to learn how to use a particular feature in the framework or IDE). 

There are some really, really phenomenal engineers in Microsoft product support who are great to work with if you have problems.  Here are some fantastic blogs that I highly recommend subscribing to from a few of them in the .NET Framework / Visual Studio space:

Tess: http://blogs.msdn.com/tess/

Doug: http://blogs.msdn.com/dougste/

Carlo: http://blogs.msdn.com/carloc/

Rahul: http://blogs.msdn.com/rahulso/

Jerry: http://blogs.msdn.com/jorman/

Johan: http://blogs.msdn.com/johan/

Todd: http://blogs.msdn.com/toddca/

If you ever run into a problem you can't figure out, or have an issue with a production application that you want immediate help on, give Microsoft product support a call and you'll have someone like the folks above attach a debugger and help you figure out what is going on.

Thanks,

Scott