In rev 176, Anonymous inner class in atg.adapter.gsa.GSARepositorySchemaGenerator attempts to over-ride the doInAutoCommit method of the AutoCommitable interface. This prevents the project from compiling.
This is a fundamental Java 5 error. Methods in interfaces cannot be over-ridden, only implemented. It's unfortunate that Java doesn't have an @Implements annotation to ensure that a method really does implement something instead of just being a newly added method, but it doesn't.
The solution is to remove the @Overrides annotations. See attached file.
Fixed version of GSARepositorySchemaGenerator.java