Thanks MistyLaraPrincess!

Now I am here, let me put in a little tip before this thread disappears in a silent corner ;-)

If you simulate dynamic cloth in the cloth room you probably keep changing those settings until you get the best result. But what if you realise that that best result was actually 6 versions back and you can't remember the settings....

Best practise is to simply save the morph every time you get a decent result. How?
Put your timeline on the frame where you want to save the morph of the cloth (not necessarily the last frame). Make sure the dress is selected, click the object dropdown menu and select "Spawn Morph Target". Now your dress will have an extra dial for the morph you just saved. Turn the "Dynamics" dial to 0 and your morph dial to 1 to see the morph.

Cheers!