First of all, thank you! I know the first Cruel Serenade game was informally translated to a number of languages, and I'm flattered that people would take the time to do so. Just want to share a few things:
1. Translation of GutterTrash is totally fine, as long as:
a. You ONLY distribute the files containing the translated text, not the complete game.
b. You make it clear that it's an unofficial translation.
c. You don't charge for it.
As long as you stick to those three, we're all good!
2. Just a note of help/assistance: GutterTrash actually contains the full maps and text of CS1, so I can refer back to them while doing various programming things (these take up almost no extra space). As a result, do NOT translate straight-through, as you'll be wasting an enormous amount of time on things the player will never see. Pay attention to what you're translating: with the exception of one scene and lead-in, if it mentions boars or ear clips, it's probably this hold-over material. Just a heads-up to save some time.
And if you do complete a translation project, let me know! I love to see what people are working on.