ExecToolManager.startTool(InterviewParameters p) does not correctly initialize tool with the values found in p. It opens an uninitialized ExecTool.
I tried writing a demo test for you, to demo this bug. The code is attached. I think it shows the issue, but if I poke around much I start getting too many exceptions.

The intent of the test program is to create an initialized Parameters object and then open it in ExecTool and demo that the tool has lost the parameters.