The recent Windows release for April 2014 Patch Tuesday, more attributed as Windows 8.1 Update 1 than anything, is also a big update forR2. The update is truly more of a cosmetic patch, enabling better keyboard and mouse functionality, than a set of major operating systems enhancements.
Still, many have questioned whether or not installing the update on Windows Server 2012 R2 would affect any of the other critical applications and services running on the servers.
For, System Center 2012 R2, the update is fine, and Microsoft has released a supportability statement via a KB Article (2949669) to assure customers that KB2919355 should be fine to install.
The KB Article reads:
System Center 2012 R2 components are supported on the April 2014 Windows Server 2012 R2 Update (KB2919355). The update can be applied to the latest System Center 2012 R2 workloads deployed before or after the update is offered or installed using your preferred distribution channels.