Karvanit, is this topic closed with no results?
Summing up, there is not only problem with zero. AFAIK, in order to use really correct language forms, you should use more than those three forms you have mentioned at the start. And what is used in different games, is also not correct. You have assumed incorrectly that the only possible differences are between a singular and a plural form. This is not true in languages with dual (Slovene has different forms used with 2) and with cases (most Slavic, for example) as various case forms may be used with such or another numeral. As a Polish native speaker who know also Russian enough well, I can share my observations with you.
Let's take units and soldiers. In order to make fully correct forms, we should have at least the following variants:
- 0 sztuk, żołnierzy
- 1 sztuka, żołnierz
- 2, 3, 4; 22, 23, 24; 32 ... 94 sztuki, żołnierzy
- 5-20, 25-30, 35-40, ... 95-100 sztuk, żołnierzy
- 21, 31, ... 91 sztuk, żołnierzy
so at minimum 5 different variants. The list of 5 different forms is going to be universal for now (and not only Polish-oriented) but it is quite possible that would not be enough when we added Slovene which uses separate dual forms.
I have separated 21, 31, 41 ... from 5, 6, 7 etc., taking Russian under consideration: in that language numerals 21, 31, ... 91 behave just like 1 (so with singular, not like in Polish). Be aware of 11, 12, 13 and 14 - they behave differently than 21, 22, 23 and 24 (in both Polish and Russian).
However... as you can see, there are words used in 3 different forms (sztuka : sztuki : sztuk) and words with only two forms (żołnierz : żołnierzy). As now, STR_DAY_1, STR_DAY_2, STR_DAY_3 are enough for fully correct Polish - as "day" has only 2 forms here. But it is still not enough for Russian! - as I can see in the language file, now the "general plural" form is used there - but this form is, frankly speaking, incorrect to use with any numeral ({N} Дни instead of 0 дней, 2-4 дня, 5-20 дней, 21 день, 22-24 дня, 25-30 дней and so on, with only 1 день fully correct).
Which is more, if you want to translate "Units: {N}", you do not need numerous forms, as one general form may be used with all quantities. However, in order to translate "{N} units" correctly, you will have to use those 5 listed above, universal different strings.
Reassuming: I do not think there is a need for creating many different variants for every string with a quantity. Perhaps you should rely on translators' requests, and when there is such a need, make variants of a given string only, as many as needed.
