The flash menu's works with any kind of normal themes, only that you have to edit the theme file...
Rename it to *.tar, get inside ans in the *.xml file make this change:
<?xml version="1.0"?>
<!-- Created with Sony Ericsson Themes Creator -->
<Sony_Ericsson_theme version="4.5">
<Desktop_style Type="File" Source="your_flash_menu.swf"/>
Save the *.xml file, remake the *.tar archive, now rename it to *.thm and voila you can use the flash menu (your_flash_menu.swf) :)
If you dont understand you can find a better post fully explained here on the forum ;)
Cheers.