ok here i summerise for u

u will need

1) power archive
2)Xml editor
3)current flash theme and desired theme

now open the current theme with power archive and look for file theme.xml

open the file theme .xml with xml editor

and look for following line
<Desktop_style Type="File" Source="activeblue.swf"></Desktop_style>

in above case the active.swf is being used in current theme as flash menu

copy the line as such and open the other theme file with power archive first and then open theme.xml with xml editor and paste this line or replace this line in other theme ...

save changes and exit the xml editor

also exit the powerarchive it will as you to save the changes ...

now transfer the 2nd theme to phone and activate it the new theme will be using same flash menu as the previous theme was........