I'm working on adding the characters from this game:
http://circus.nandemo.gr.jp/sakuhin/vc/contents/character/mikoto.html

I have no "translator flair" so... ミコト　ミュラー reads to me as Mikoto Myuraa . I'll do the same literal reading for all, so any tips on how to translate them better, please let me know and I'll correct these names. Thanks!

Added:
http://www.animecharactersdatabase.com/publisher.php?id=1994



[ Edited Jan 12, 2009 ]

私は日本語を少し読むと書くをできます。あなたも？

well, the only one that I can help out on is that last one. A lot of times L's in the english language are translated in japanese with the "R" sound, so "Reo" is most likely a "Leo".

Below would be my suggestions. Most of them I've got a pretty good reason for spelling them the way I do, but I'm afraid the name "Kylane" is complete and utter thumbsuck. Of course, as I'm sure you realize, without some sort of official source we're just guessing.

レオ・リチュアル Leo Ritual
キリエ・レイソン Kyrie Léison*
ミコト・ミュラー Mikoto Müller
エリス・リチュアル Eris Ritual
カイレイン・プリエーラ Kylane Priella
レジーナ・アラマンタイン Regena Alamantine

*: From "Kýrie, eléison". All we're missing is one エ.

[ Edited Jan 13, 2009 ]

Hmm, hmm, I think you're both right on those readings. Thanks!

There seems to be an increasing trend with anime and games in Japan: more and more of them have characters or an entire cast of characters with non-Japanese names. Expect the next set of names shortly. ^_^

[ Edited Jan 13, 2009 ]

私は日本語を少し読むと書くをできます。あなたも？

Bring it on. I actually enjoyed that.

Mind you, I think Japanese game developers usually make a decision beforehand. If the story is set in a foreign country or fantasy universe, they usually go for non-Japanese names, whereas if the story is set in Japan, they mostly keep them Japanese. There are exceptions, of course.

Name updates applied. Next is...

http://18.animecharactersdatabase.com/jp/publisher.php?id=1997
http://mana.product.co.jp/mare/index3.html

Irugitto Naitomea
Merussa Naitomea
Nanana Masano
Ruri Fujino

brobb, if you ever want to preempt me on the name updates, you're free to do so. ^_^

Kyareshi, awesome observation. You're right, those types of settings tend to have characters with foreign names, now that I think of it. And there does seem to be more anime and games in those settings.

[ Edited Jan 15, 2009 ]

私は日本語を少し読むと書くをできます。あなたも？

Here's what I get.

イルギット=ナイトメア Illgit Nightmare
メリッサ=ナイトメア Melissa Nightmare

I don't see anything wrong with your romanization of the kanji names. By the way, you seem to have misread メリッサ as メルッサ (probably because of her nickname メル).