I opened a ticket with Symantec for clarification on how to disable Tamper Protection on Windows Server 2008 R2 when using SEP SBE 2013. There is a bit more work involved, but it is a quick operation:
1) Make a backup of profile.xml located in C:\Program Files\Symantec.cloud\AntiVirus
2) Edit the backuped up profile.xml and change the following items to reflect the settings below:
<SilentModeEx Enable="0"/>
<UserInterface HideSystemTrayIcon="0">
3) From the command prompt, navigate to C:\Program Files\Symantec.cloud\EndpointProtectionAgent\ and run the following command:
smc -importconfig <path to modified profile.xml>
4) If the SMC GUI icon does not load in the system tray, log off and back in.
5) From the GUI navigate to Change Settings -> Client Management (configure settings) -> Tamper Protection
6) Uncheck the box to disable Tamper Protection and click OK.
At this point it should be possible to modify the LaunchSMCGui registry entry. To re-enable tamper protection just import the original profile.xml.