Hi,
What do you mean : "if a swf works a button or hotspots depends also on the swf itself,it can work but it must not..." ?
a swf can be a full flash complex program, if it's just an image or animates there should be no problems, but if the swf draws something dynamically, and maybe has own resize events, or changes the layout of the internal drawing stage, then it could be a problem,
Ok, i answer to my question. To see the button :
blendmode="screen"
yes, the
blendmode="invert" was the problem

you could also use -
blendmode="normal" - to display the swf without any blending effect,
best regards,
Klaus