Я как бы не профи, но error - это "физическая" ошибка. Тут больше подойдет mistake

The same are the petals, too, falling with perfidious indifference.

I don't consider it to be an actual error per se, so much as just somewhat coming across as overly high-brow or pretentious.

I'm not sure what exactly I'd change it to either though, but perhaps something more along the lines of.

The same are the petals, too, falling like clockwork.

"I would have turned it off long ago, but then I would have certainly cooked alive by the heat."

Feels slightly awkward, almost like it is implying that you'd have cooked something as opposed to having been cooked yourself.

I'd just change it to

"I would have turned it off long ago, but then I would have certainly been cooked alive by the heat."

"I gulped the water down greedily, spilling half over myself."

Generally spilling over implies that something overflowed as opposed to spilled due to recklessnes.

I'd just change it to

"I gulped the water down greedily, spilling half on myself."

"Next morning, I had to go school."

At the very least it should read to go to school, but the preposition at the beginning is awkward as well.

Either

"In the morning, I had to go to school."

or

"Come morning, I had to go to school."

would flow better

I'm not seeing that many errors in the translation, but there are some typos I've noticed. It should be "Catherine" instead of "Catherina" in the sentence "without even turning her head, Catherina walked past us" and it should be "also" instead of "laso" in the sentence "It was laso quite fortunate that Catherine occupied the desk closert to the door". I haven't gone through the demo in Russian to check, but in that same sentence "closert" should be either "closer" or "closest".

This is looking great. Can't wait for the full release.

Hello, i would like to know if the game will have a translation in Spanish.
I loved everything Everlasting Summer thanks to the translation in Spanish. And this Demo has a lot of potential.
I know there are several difficulties, but I hope that the game will be successful... and have the translation in Spanish eventually.
Thank you so much.

Maybe, eventually...

In the intro at the very beginning, an info box explains "Sakura Blossom", whilst the actual text doesn’t use that term at all. instead saying "These falling cherry petals...". This seems disconnected and irritating. Either remove the box or actually use the explained term.

Скачал демку, кликнул на English в выборе языка, в краткой инструкции написано "ПКМ" вместо "RMB" или "Right Click". Если это не какая-то пост-постирония, пофиксите пеже, а то будет неловко ^_^
UPD: Если зайти в раздел Endings (по крайней мере в самом начале), у меня пишет "Seen<code></code> episodes", не думаю, что так задумано
UPD2: В разделе Help -> Notes заголовок - "Сноски", вместо "Notes" и, хз, так надо или нет, в Credits не переведены имена на латиницу, это нечитабельно
UPD3: Если поменять язык в ходе игры, интерфейс переводится только частично

https://cdn.discordapp.com/attachments/453676085570174976/743232287243501648/20200812_181929.jpg

"The day when I had to something"

i was just about to ask where I could submit these. You might want to add page numbers in the demo version that can be removed for the full release so people can report these easier

You can write here.

Just wanted to note that if you still need anyone with ENG-RUS-UKR languages for any of your projects, I'd be glad to help.

Сценка с концертом в баре. Пропущен пробел в фразе "Богатые уже с жиру бесятся!Ладно просто бренчать на досуге, но такое..."