I don't know whether there is a difference between old and new missions in regardence to translatability (is that a word?). However, regarding the wiki The Outpost is already converted to the I18N format and some translations have been provided, although not a russian one. (It seems there are no russian translations whatsoever even though there have been attempts in the past, but that is based on the wiki which may be outdated in that matter).
If you want to provide translations I would furthermore suggest to use the english.lang string file as starting point and translate the strings inside those files instead of running the script on the mission pk4 again. I wouldn't blindly assume that the results are always the same, so strings might get mixed up. Also note that when translating you have to keep the amount of space required by the strings in mind, as they could otherwise get cut off ingame. You'll as well as other russian speakers have to check that ingame.
Regarding the tooltips. They are part of the loading screen gui I guess. This feature was added after the script was written. As the member who wrote that (Tels if I am not completely mistaken) is no longer active, the script probably haven't been updated for a while now. You can alter that manualy, I guess. Note, though, that any change on mission pk4's need permission by the respective mission authors.