Any update on part 3 and is there a new version available?
As of right no, no. Part 3 has not been released yet.
The good news is that the devs just have to code and put the pieces together.
Furthermore, they are happy to have more fans and contributors.
Right now all devs can also be given separate donations aside from subscriptions on their blog page.
Furthermore, another city you might habe known from the previous game is added, namely "Hamel". Here's the whole article (it's all in Japanese):
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On sending messages to them: please send the messages in Japanese, if you have any suggestions, ideas or questions. It takes less time and effort for them to andwer messages in Japanese since they cannot spesk English very well.
If you're interested in translating the game, they might like to have a question regarding that, also preferably in Japanese. Explaining some benefits will also help, as they like to have a wider audience.
If you are going to translate, I hope that you have learned Japanese grammar and kanji well with a legitimate course or otherwise Duolingo and Wanikani.
With Wanikani, you can learn Japanese kanji and vocubalury very well. Duolingo is better for the grammar, but also look for other courses that might help you. Plus read Japanese manga!