Scratch

What happens is with this program I am making, when I click the green flag, the outside of 1 script out of 2 scripts become red instead of white or transparent. What does that mean? Does it mean that the script can not be read or something? Or does it not make sense? Or is the scratch program having a glitch telling me that  Scratch is a horrible program? What is the problem? Oh and here is the script:

Light's script

When green flag is clicked
Forever
     Set x to variable "saber's direction" divided by variable "saber's x"
     Set y to variable "saber's x" plus 60
     Point in direction variable "Saber's direction"
End.
(This is the red outlined script)


Saber's script

When green flag clicked:
Forever:
   Point towards mouse-pointer
   If key up arrow pressed?
      Change y by 2
   End.
   If key down arrow pressed?
      Change y by -2
   End.
   If key right arrow pressed?
      Change x by 2
   End.
   If key left arrow pressed?
      Change x by -2
   End.
   If Space pressed?
      Set x to 0
      Set y to 0
   End.
   Set variable "Saber's direction" to direction
   Set variable "Saber's y" to y position
   Set variable "Saber's x" to x position
End.

Variables:
Saber's x
Saber's y
Saber's direction

So that is the script so . . .what is the problem?And I am in 4th grade so I may not understand something.