Yes, AdXpansion now supports Flash banners.

You MUST use the clickTAG variable within your banners.

Here is an example of the syntax

on (release) {
if (clickTAG.substr(0,5) == "http:") {
getURL(clickTAG, "_blank");
}
} 

IT IS IMPORTANT THAT YOU SPELL "clickTAG" EXACTLY AS SHOWN.

DO NOT hardcod the destination url within the flash banner.

Banners not using the clickTAG variable or not using it properly will  be rejected. 

Maximum file size is 300k but we prefer that your flash banners to be max 100k.

Upload .swf files and not the .fla.