I'm translating this book, and the character's full name pops up as " クロウディア＝マッキェネン". I managed to translate the first name as Claudia, but I don't know if I should use McCunnen, McCullen, or some other possible translation for her last name, and thusly I am in need for some advice.
Here is a screenshot of the official site of the X360 port (Flash-only):
So she is officially Claudia McCunnen.
ネ always corresponds to the "N" consonant, not "L". Even without this site, we can say McCullen is not really a valid transliteration.