Bob,
Yes, they are difficult even when carefully handled. Mine look like Hell toward the end of the sailing season here in the US but still perform well. the 1.4 mil is aweful but awesome on the water above 2mph.
I pickup a nylon like tool at a fabrics store that think was used for large hemming. Not sure but is about an inch wide and four long to a point. It is flat on one side and the other is cambered in a flat arc. I have used that side to take out some creases but it hardly looks better. But that is the only recommendation I have heard about.
Whereas, I sail about a dozen times a year with those sails, I just gave up and replace them each year. They look bad but work well.
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