Testing beta 8 with two different virtual environments:
Ubuntu 14.04.1, FreePBX 12.0.1rc11, Asterisk 11, PHP 5.5.9
Centos 6.5, FreePBX 12.0.1rc11, Asterisk 12, PHP 5.3.3
WUC ver. 2.11.3 (stable) works fine on both. WUC 2.11.4beta8 works on Centos but does NOT work on Ubuntu. When installed on ubuntu, the FreePBX GUI comes up blank. Thinking it is probably related to PHP ver. 5.5.
The problem is in functions.inc.php, the Ubuntu GUI starts working again once it is deleted.