Are you attempting to read from V8...?
Did you program the V2 BBx config files (Program All)...?
Are you using the latest version of the EFILive software from the main Downloads page? Try using V8 to read it as well.
~Erik~
2013 Sonic RS Manual - 1.4L I4T E78, tuned, turbo mods, etc.
2008 TrailBlazer SS 3SS AWD Summit White - LS2 E67/T42, bolt ons, suspension, etc.
2002 Chevy TrailBlazer LT 4X4 Summit White - 4.2L I6 P10, lifted, wheels, etc.