I'm currently working on making parameters have options you have to select from. Currently the only executor that understands this is CyberintegratorTool. If you grab the latest version of the jar file cyberintegratortool_20090925 you can now create a Parameter that has a list of options the user can select from. public Parameter(String id, String name, String description, String value, String... options);
I'm slowly in the process of adding this to the matlab and command-line executor as well.