I live in the UK and have major issues with my fondant cracking at the edges, i have tried every fondant from supermarket own to regalice, covapaste and renshaws covering paste and ALL get cracks on the edges, it drives me mad. they are not huge cracks just hairline ones which im sure others dont notice but to me they stand out like sore thumbs!! I colour all my own fondant so wondering if i am over kneading it? ive made my own fondant and it didnt crack but i really dont enjoy or have the spare time to make my own.
i have tried using loads of vegetable shortening when kneading to stop it drying out as much, ive cut the edges so they are not sharp angles. I also cant seem to massage the cracks out!
Have you tried PME ? I find it works best for me . Tried the others you mentioned and found it better