1. 'MAD-uh-lin' or 'MAD-uh-line'
2. 'MAD-uh-lin' or 'MAD-uh-layn'
3. I only know one (
Madeleine). I don't think it's too common.
4. I prefer the 'MAD-uh-lin' pronounciation, which is probably similar to the one you're saying about. Personally, I don't like the 'line' ending for names, apart from in
Caroline. For others (
Emmeline,
Rosaline), I tend to say it as 'leen' or 'lin'.