ERROR:Compxlib - Compxlib does not support riviera version prior to 8.3. Parsing through the path setting on your system we have identified that you are using riviera '2011.10.77'. Please contact Aldec to upgrade to a supported simulator version. If the path setting is incorrect, please ensure that you are pointing to the latest version and re-invoke compxlib. The list of supported simulator versions are listed in the Simulation Chapter of the Synthesis and Simulation Design Guide on /http://www.xilinx.com.