When calling CoverageManager.exit() from a Flex app, there is an error just before the coverageManager tries to shutdown the application:

ReferenceError: Error #1065: Variable NativeApplication is not defined. at global/flash.utils::getDefinitionByName() at com.allurent.coverage.runtime::CoverageManager$/checkForExit()[C:\work\flex\3.0.x\frameworks\projects\utilities\src\com\allurent\coverage\runtime\CoverageManager.as:203] at com.allurent.coverage.runtime::CoverageManager$/handleStatus()[C:\work\flex\3.0.x\frameworks\projects\utilities\src\com\allurent\coverage\runtime\CoverageManager.as:196]

Added a try/catch in version 0.50 -- this should now be fixed.