Original text - Người Hy Lạp cổ đại - Δικαιον εστι μεμνησθαι θεον τον ευ πραττοντα....

θεου --> θεον

Moreover, though it is quite readable, it is also without diacritics which there are many in original Ancient Greek texts.
Is it allowed to submit text without diacritics...?
When I translate into A.Greek I always put them into letters, so I'm surprised it doesn't work vice versa...

For Latin and ancient Greek we do not demand texts to be typed with their diacritics.
It goes differently when it is about languages that are currently used, spoken and written, except if diactritics are not currently used in the nowadays language (which is the case with Hebrew , for instance).

I hope I answered your question?

Well, Francky, I don't know if we should accept Ancient Greek without diacritics. In this case lack of them rather doesn't disturb us to understand the source, but sometimes one "diacritic" can change quite a word and it can be very needed...
For example:

καλὴ - a victory
καλῃ - to a victory

so if we type καλη - it can disturb understanding the sentence...

It can change also tenses and moods:

á¾–Ï‚ - ind. impf. act.

ἦς - con. praes. act.

I could give you a lot of similar examples...

Thanks for your input!

Ok, As an expert you rule. If you think diacs must be used, you can demand them to be used in the translations. About texts submitted in ancient Greek, we can either set the request in "meaning only", or ask requester to add the diacs, a third possibility would be that you add them if ever requester doesn't know the source-language at all.