Oh hey, glad to hear from you, and glad you're enjoying the games! I hope you don't mind me leaving this in English; I'd just be running it through auto-translate anyway, and whatever you have set up on your browser is probably as good or better.
Really appreciate the kind words. I do what I can, but knowing people care certainly helps as I power through these long development times. So on to the questions:
I use RPGMaker MV. In my opinion it's the best version. MZ is a minor upgrade that adds some neat little things (for example when you program an autopath for a character, it actually visualizes it for you instead of you having to hold it in your mind), but it's not essential and I don't want to risk breaking old plugins. The version after MZ turned RPGMaker into a plugin/addon for Unity, which is a horrifying and disgusting idea.
I refer to the games as "Chapters", and the plan is, and has been, to eventually have 5 (the one that's currently in development would be #3). We'll see if I manage to get that far though. Each game is designed to be its own story as well though, so even on their own they should be fun enough.
As for other games, we'll have to see. There are a lot of options and possibilities out there, but things change fast, year to year and even month to month. We'll see where I am when and if I finish this series.
No problem asking about translations though. The way that works is simple: people are free to do fan translations, and if they like they can submit them. If I take a look through the translation and it seems stable/decent quality, I share it. So the answer is that there will be a Russian translation as soon as someone makes one, which hasn't happened yet to my knowledge. I think there was talk of one at some point, but it never happened. If someone wants to though, the files are all there, unencrypted text, and using something like Translator++ can help you keep track of your work and avoid typos that break the formatting. No rules other than try to be accurate, and human translation is preferred. If you use more that 20% machine translation material, be sure to say so.
And again, thanks for your support, and kind words. Much appreciated.