If you want to customize a build script template for the use with the CommandLine, which is the equivalent of the Talend Studio without GUI, go to the directory where the script file is stored, for example, <studio_installation_directory>\workspace\<project_name>\process\CA_customers. Then, customize the script file according to your need.
The modified script file will be taken into account when a Job is built with the Maven option activated.
There is no direct customization to the global build script templates for use with the CommandLine. As a workaround, you can add template files in the root directory <studio_installation_directory>\workspace\<project_name>\process\ for Jobs, and then and modify the XML files. Note that these script templates will apply to all Jobs in all folders except those with their own build script templates set up.
For more information about the CommandLine, see Appendix A of the Talend Administration Center User Guide.