[Hitman]

If you simply want to change the date in which the mission plays, it is easier to open the mission dsf file with Notepad and search in the first block foir thata data. So you change it manually, save, and that's all.

In Korralle there is also a screen to do that, but I recommend hand-tweaking the file if you are doing only minor changes. Korralle is better for scripting missions from scratch than for tweaking them, because it tends to screw a part of the scripted mission when saving.

Hope that helps