Gimp core error

Hello everybody,

I'm completely new to fu-scripting,

I have a problem using scrip-fu-distress-selection, it causes the following error :

(gimp:3091): Gimp-Core-CRITICAL **: gimp_image_set_active_channel: assertion `channel == NULL || gimp_container_have (image->channels, GIMP_OBJECT (channel))' failed

GIMP-Avertissement: Plug-In '(null)' left image undo in inconsistent state, closing open undo groups.

The script I made is very simple : select black color, feather the selection and distress it. It works well without the distress part. 

Any suggestion that would help me out ?

[code]

(define (simple-unsharp-mask filename)

   (let* ((image (car (gimp-file-load RUN-NONINTERACTIVE filename filename)))

          (drawable (car (gimp-image-get-active-layer image)))

(width (car (gimp-drawable-width image)))

         (height (car (gimp-drawable-height image))))

(gimp-context-set-background '(98 123 0))

(gimp-context-set-foreground '(144 176 17))

(gimp-by-color-select drawable '(0 0 0) 0 2 1 0 0 1)

(gimp-selection-feather image 10)

(gimp-selection-sharpen image)

; (script-fu-distress-selection RUN-NONINTERACTIVE image drawable 127 1 1 1 1 1)

(gimp-edit-blend drawable 0 0 0 100 0 0 0 0 0 0 0 0 0 width height)

(gimp-selection-invert image)

(gimp-context-set-background '(255 255 255))

(gimp-edit-fill drawable 1)

     (gimp-file-save RUN-NONINTERACTIVE image drawable "/home/alexis/img2.jpg" filename)

     (gimp-image-delete image)))

[/code]

Alexis.

NB : the script is used in terminal-mode, not as a gimp plugin.