Currently in JMP 8, using script, i am able to add data tables to Project without any issue using the command:
EXPJ =New Project("New Project");
dts = data table("MyData");
EXPJ = add window(dts);
However, i am having trouble to add a Script window to the project. By just dragging the script window to the project it works. I could save the project with a script (.jsl file) attached. But i could not attach it using script itself just like the data tables.