Thats the first step, what you have there. Click on "Update", than the wrapper installs. Now WineSkin is ready to work on your system.
Click on Create new blank wrapper. WineSkin builds a wrapper now. Install all you get in the following windows.
When ready you have an .app! So your Windows Program can look like a OSX .app. In this package, there is another app: a helping program. First time you click on your wrapper this opens automatically. Open this one.
Press on install software. "copy a folder inside", select it.
When pressing on "advanced", you'll get more buttons:
Under the first tab you can select your copied .exe, and config under associated extensions what happens when opening an .mlv with this app.
Under "Tools" you'll find "winetricks". There you search under dll for "Visual Basic 6 Runtime". Install it.
That should be all. MLV Producer runs than nearly like an native OSX application.
First time using it, it may be a little confusing. But really... it is very simple and runs with a lot of windows programs.