Did you to redo you chart from scratch? In some of my charts made before there was the markers options although the markers are working the rest is not so redoing it from scractch mad eeverything working.
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I just tried re-doing from scratch bu still no luck. Pretty strange. There must be something I'm not doing right if it works on your side. Maybe Microsoft will find the bug which disabled the "Legend Style" option which was included a few months back.
Thanks for keeping an eye on this thread BTW. Much appreciated.