A picture speaks a thousand words, but 'marshmallow' stuff might mean scale infestation - looks like a brown thing with white stuff all round the edges, about half the size of your little fingernail, sometimes bigger. Google 'horse chestnut scale' for images to confirm. If it is that, get some disposable cloths and a bottle of methylated spirits - moisten a cloth lightly with the meths, rub over the woody parts to remove the scale, changing cloths when they get mucky. Do not get the meths on the leaves. Check any woody fence and the pot (if its in a pot) because this form of scale gathers in places like that too.

Shrivelled leaves are likely due to excessive wind or sun, or drought.

Thanks for your response that's what it looks like