Swf increase size mystery publishing into Flash 8 and Flash CS4

Question

Hello,
i discovered recently that a swf build with Flash 8 IDE, published for Flash Player 8 get a different size when published with Flash CS4 IDE.
You can reproduce that effect with all sort of swf.
I did a report for each publish (same .fla into Flash 8 IDE and Flash CS4 IDE)
The result was : all vector graphics, all fonts, all bitmaps, all actionscript code increased
From test.fla, i did one key frame with :
- a dynamic TextField with some simple chars in it = "Test Chars",
- a simple shape with brush tool
- and one movieclip with an ordinary circle
Size report from Flash 8 :
test.swf Rapport sur l'animation
Image #    Image octets    Total octets    Séquence
      1          14419          14419    Séquence 1 (Image d'exportation des classes AS 2.0)
Séquence                        Forme octets    Texte octets    ActionScript octets
Séquence 1                           86           132                     0
Symbole                       Forme octets    Texte octets    ActionScript octets
clip_circle                           69             0                     0
Nom de la police                 octets        Caractères   
Arial                         14056     !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxy z{|}~ˆ˜–—‘’‚“”„†‡•…‰‹›€™
Size report from Flash CS4 :
test.swf Rapport sur l'animation
Image #    Image octets    Total octets    Séquence
      1          18932          18932    Séquence 1 (Image d'exportation des classes AS 2.0)
Séquence                        Forme octets    Texte octets    ActionScript octets
Séquence 1                          103           174                     0
Symbole                       Forme octets    Texte octets    ActionScript octets
clip_circle                           91             0                     0
Nom de la police                 octets        Caractères   
ArialMT                       18467     !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxy z{|}~ˆ˜–—‘’‚“”„†‡•…‰‹›€™
Does somebody knows something about this strange phenomen ?

Answer 1

Didn't look at the file size of the FLA, just the SWF as I didn't even necessarily resave the CS4 as CS6. No edits were made, I tried it with a simple open and publish just to make sure I wasn't doing anything to change the file and the resulting file was heavier (kb).
I looked through the size reports and saw that while image compression was better in the CS6 version, the fonts were all heavier than they were in the CS4 version and this put it over the 40kb limit.