Puzzling problem: export gif

[Dom]

Hi!

I have a puzzling problem...

I converted a huge image HC database to Rev -- no problem here
The HC stack was a very simple, just an image depository
But it is a very large one, with a 44 Mb footstep -- so I considered
exporting the image to Desktop database, with images in nested folders.
Moreover, it takes a very looong time to see inside the stack with the
Application Browser ;->

In each card, there is a path field, containing some keywords.
I gathered these keywords into a text file, and created the folders with
an ancillary stack [two levels depth, though... there is as much as 7
keywords for some cards!]

Then, I tested a button to export the image in the card to a GIF image
(as there are only B&W bitmap images in this stack)
A test stack worked well, after some tweeking.

I copied the button onto the stack to parse...
Oddly this worked fine for 10 cards -- and stopped to work, with this
error message:

Type    export: can't write to file, mask file, or container
Object  export gif
Line    export image 1 to file timage as GIF
Hint    CULTURE/Codes spécialisés/image14.gif

The script:

on mouseUp
  
  set the itemdel to ":"
  lock screen
  lock recent
   
  repeat 10 times -- for testing, but fails on the *next* card

    get fld path
    put item 1 of it into d1
    put item 2 of it into d2
    put d1 & "/" & d2 & "/" into tfolder
     
    set the filetype to empty
    put tfolder & "image" & number of this cd & ".gif" into timage
    export image 1 to file timage as GIF
    if the result is not empty then answer the result
     
    go next
    
  end repeat
  
end mouseUp
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