Defining external material product on several lines

[Philippe Grosjean]

Using LyX 1.6.3 Mac OS X, I am not able to define Product on several 
lines (as the example in the Customization manual). Here is my definition:

Template Rcode
        GuiName "R code: $$FName"
        HelpText
                Insert R code inside a R-Chunk (Sweave document).
        HelpTextEnd
        InputFormat R
        FileFilter "*.{R,r}"
        AutomaticProduction false
        Preview Off
        Transform Extra
[...]
        Format Ascii
                TransformOption Extra  ExtraOption
                Option Pre "<<$$Extra>>="
                Product "$$Pre
$$Contents(\"$$AbsPath$$Basename$$Extension\")
@"
        FormatEnd
TemplateEnd
Using this, I got only the string equivalent to $$Pre printed in my 
document. If I put everything on one line, that is:

Product "$$Pre$$Contents(\"$$AbsPath$$Basename$$Extension\")@"

it works fine (except the '@' that is not printed)... except I need to 
include line feed between the three elements for correct noweb 
formatting of my output!
May be is it an alternate way to include line feed or @ in the product 
(I have testes \n and \@ without success)?
Best,

PhG
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 ) ) ) ) )
( ( ( ( (    Prof. Philippe Grosjean
 ) ) ) ) )
( ( ( ( (    Numerical Ecology of Aquatic Systems
 ) ) ) ) )   Mons-Hainaut University, Belgium
( ( ( ( (
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