BerghausMen's Deluge Waterproof Breathable Overtrousers

Are they heat resistant as my last waterproofs stuck to the exhaust

what is the size of the extra large Berghaus Men's Deluge Waterproof Overtrousers

How big is the difference between Large Long and Large Regular? I bought Long and they are too long, so wondering if i should order Regular instead.

can the ankle be adjusted?