it's impossible to define custom interceptor this way:
Configuration config = new Configuration();
List<CustomInterceptorConfig> customInterceptors = ....;
config.setCustomInterceptors(customInterceptors);

The problem is in the class org.infinispan.config.OverrideConfigurationVisitor. Override() method overrides everything but customInterceptorsType field. I think a single line should solve this problem:

overrideFields(customInterceptorsType, override.customInterceptorsType);