Main menu:
use media_loop()

Code:

---

//Volume for media
define MenuVol, 100;
//Sound File
string sndMMBG = "Menu.mp3";
//
var BGSound;
Function StartMenu()
{
    BGSound = media_loop(sndMMBG, null, MenuVol);
}
Function EndMenu()
{
    media_stop(BGSound);
}

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Texture for footsteps:
Use a trace from the player to the ground. You can either name your textures starting with a x digit code such as dirtblabla.tga or graswhatever.bmp. Then in your trace include the flag scan_texture.

then you'd use string comparisons to get the tex name, copy and clip it to 4 (or so) digits, then use IF statements to figure out which sound to use...

Code:

---

//volume for footsteps
define StepVol, 100;
//
string tstr;
function PlayFootstep(Texname)
{
    str_cpy(tstr, Texname);
    var i;
    i = str_len(tstr);
    if (i < 5)
    {return(0);}
    i -= 4;
    str_trunc(tstr, i);
    //
    if (str_cmpi(tstr, "dirt"))
    {ent_playsound(my, sndStepDirt, StepVol); return(1);}
    if (str_cmpi(tstr, "gras"))
    {ent_playsound(my, sndStepGrass, StepVol); return(1);}
    if (str_cmpi(tstr, "metl"))
    {ent_playsound(my, sndStepMetal, StepVol); return(1);}
    return(2);
}

---

Use:
call PlayFootstep(tex_name); after using a trace with the scan_texture flag.

returns:
0: the input string had less than enough characters
1: function ran successfully
2: No matching sound could be found

Code:

---

Function Footstep()
{
    vec_set(temp, my.x);
    temp.z -= 500;
    c_trace(my.x, temp, scan_texture);
    PlayFootstep(tex_name);
}

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