Thanks for the help guys! I followed this topic instructions to get a horizontal scroll bar on a estructured text frame at my dialog. Just for feedback, this was the code that worked for me, following the Samatra´s last post steps:
_control = findDisplay 10 displayCtrl 1100; // use your idd and idcs for the structured text control as defined in your dialog.
_myControlPos = ctrlPosition _control; // array with control position and heigth of the control [x,y,z,h];
_oldH = _myControlPos select 3; // saves old heigth (point 2 at Samatra´s post)
/// Modify your text (point 3 at Samatra post)
_control ctrlSetStructuredText parsetext _Text;
...
/// End of text modifications
_newH = ctrlTextHeight _control; //save new Height of the text modified. (Point 4 at Samatra´s post)
_x = _myControlPos select 0;
_y = _myControlPos select 1;
_z = _myControlPos select 2;
_control ctrlSetPosition [_x,_y,_z,_newH]; // Set new heigth. (Point 5 at Samatra´s post). In my case, I just applied the new Heigh, not the diference between new and old ones. (It worked for my in that way. Not sure why, but I finally not used the _oldH variable)
_control ctrlCommit 0; //Mandatory for 2D controls to commit changes.
Hope it helps!
Regards,
Spikeslf.