Are you strictly working with the templates or did you program the main menu by yourself?
Take a closer look at your code and think about what you did that could cause the errors.

For the mouse. This is a function that enables/disables the mouse cursor.

Code:
BMAP* cursor_bmap = "cursor.pcx";  //Bitmap

void mouse_on() 
{ 
  mouse_map = cursor_bmap;
  mouse_mode = 2;
  while (mouse_mode > 0) // move it over the screen
  {  
    vec_set(mouse_pos,mouse_cursor);
    wait(1);
  }
}

void mouse_off() 
{ 
  mouse_map = cursor_bmap;
  mouse_mode = 0;
}


Nevertheless I would heavily recomment to make your first steps not with the templates, but by doing the scripting tutorials. Don`t make a shooter in the first place, but think a bit smaller. Do a little quiz game. Or a jump and run. And script it entierly by yourself.

Tutorials: http://www.opserver.de/wiki/index.php/Scripting_Tutorials

I recomment doing the official tutorial step by step, and then take a look at Slin`s tutorial. After this you should be able to begin programming seriously. laugh

If you just want to play a bit around and get a closer look at the editors and stuff (and want to have some fun), I recomment Realspawn`s beginner tutorial.