Based on this, it sounds like you’re having a problem with the creation of some service or other. So some code somewhere is calling a service locator’s get() method, which is then looking at the configuration (most likely from module.config.php in the VuFind module) and then failing to construct an object successfully.
Are you seeing any “previous exception” information? Often the error page for ZF2 will show a whole chain of exceptions for this type of failure, and usually the last link in the chain (the service manager failure) is the least informative. For example, if your cache directory permissions are set incorrectly, the service manager will fail to create the searchspecs reader due to an inability to create a cache manager… and this is more obvious from deeper exceptions than from service ones.