I've been working on doing text replacement for CtC for some time now myself. I will not pretend I'm anywhere near as experienced as the rest of you, as I too am stuck with most of the things that the vast majority of you guys are.
I did figure out how to do a line break in the conversational dialog scripts, and it isn't difficult to add new cues, either; so placing in English text that is true to the original translation is not at all difficult, and no shortening needs done.
I don't know how far you guys are, exactly (and I'd heavily wager you're much further along than I am), but I'd used TouhouWiki's translations to replace all 100% of the dialog, the player spellcards, and the ThC-scripted items on the Shot Select screen.
Last I checked at TouhouWiki's talk page, nobody's yet figured out the coding for the .dat files (mandatory, I am told, for doing text replacement of the enemy spellcard names); perhaps you guys know more than they presently do. I'm not technically knowledgeable about any of that kind of stuff, so I wouldn't be able to help with the de-encoding. However, I do have plenty of time on my hands, so if anybody does figure it out, I can do the text replacements very, very quickly if I am provided with a de-encoding tool so I can alter the necessary files.
In other words, I have no idea how far you guys are, and I don't know exactly how much I can really help, depending, but I'm offering help with this project's expedition, if indeed there is any I can really offer.