I think this is really fascinating too, and I’m glad you’re thinking about it, @amegaara! Basically, Psycopathic Misathrope swears a lot, but the game is supposed to be E for everyone, so he can’t use actual swearing. In fact, he probably shouldn’t even really say “screw this” except that he really does think of it like, to turn a screw, screw. Maybe I’ll replace it with “Rotate this.” or something similar. He can’t say the F-word either, but the word sounds like Fork, which also sounds like Spork, so he’s expressing the universal frustration all people feel when trying to use a lame plastic utensil to stab or cut things.
Hope that helps your translation efforts. Basically, I would advise replacing his lines with a humorous exclamation of aggravation.
I can’t talk more about Sid at the moment, but perhaps more will become clear in context. 
Yeah, this is probably because the font we use doesn’t support those characters natively, and the browser is falling back on some other font. If you find a font that really works for your translation efforts and that looks good, let us know… You should be able to replace the font in the css/less files, if you can see them.
It’s really really cool for Team Radiant to see the game in so many languages. Thank you all so much. We are all charged up for the week now!