1) ArmA briefings are the same in technique as in OFP, visually different though. I've attached a working briefing.html of myself.
2) OGGs still work, tutorials of OFP should work too.
Just in case:
Description.ext
class CfgSounds
{
sounds[] = { STR_I1,STR_I2 }
class STR_I1
{
name = "STR_I1";
sound[] = {"\sounds\STR_I1.ogg", db+10, 1.0};
titles[] = { 1, "" };
};
class STR_I2
{
name = "STR_I2";
sound[] = {"\sounds\STR_I2.ogg", db+10, 1.0};
titles[] = { 1, "" };
};
};
Optionally (but recommended) - Stringtable.csv (in notepad etc, not in excel / word)
LANGUAGE,English
STR_I1 ,"Blablablabla"
STR_I2,"Hello."
Make sure you've got a working OGG file, same format as mentioned in the OFP tutorials about sound stuff. Playing them in the game can be done with:
unit1 say "STR_I1";
playSound "STR_I2";
The second one just plays the sound, using the first line makes a unit say something. If you drop a .WAVE file on the wave-lip converter you can make a soldier's lips move correctly.