Passing groovy 'lists' via testcase properties...

We had the same problem. The solution is here: https://stackoverflow.com/questions/44421624/how-to-pass-a-two-dimensional-list-array-between-groovy-scripts-in-soap-ui 

NOTE: Remember to run the steps from test case (not from step) as explained in above post. If you run from step the context will be limited but if you run from testcase the array will be visible in both steps (I tried and it works).