ChallengeTime Script - Error

I try to use this script http://projectdxxx.me/script/index/id/14d0738c058806c165798ff6e242f1eb. But when I try edit script (change start time) appears an error.
How to fix it?

maybe you are using Win8...There is a bug when editing text in PPDEditor in Win8.
You can edit script with FlowScriptControlTest.exe instead.(After edit in FSCT.exe, save project in PPDEditor)

Yes, I use Win8. Thank you, I will try it.