ActionScript 2 in Flash 5

I'm using Flash MX 2004 with ActionScript 2. If users have Flash Player version 5, will they need to upgrade to play the swf files?

Does anyone have any links or information on compatibilities with the different versions of Flash Player?

Thank you,
Rob

If you export the swf as version 5 Flash will complain if the codes are not compatible with that vesrion. So then you'll know.

Here is a tutorial for things that are different in MX2004 AS
http://flashscript.biz/MX2004/bugs/MX_MX2004.html

Exporting it to Flash 5 gives me errors, which help find errors in existing code.

I am concerned in choosing a feature from MX 2004, spending time coding it, then finding out that I cannot use it because it is not support for Flash Player 5 or 6.

Is there a list of features of MX 2004 that states that they are not supported in version 5 or 6? Is there a list of features in Flash 6 that are not supported for version 5?

Thanks,
Rob

Everything new is not supported for other flashplayers, for example the new components and some AS.