@swamp
for every keyframe, you can easily add a sound at the properties section. import the sound to the library (was F11 at earlies versions).
that can be music or sfx too, but it ofc increases the file size.
i also did a flash animation for trem(back in '07, but now i see links are borken... :-O
will check back if i can find it...:-P
there--->
http://archive.mercenariesguild.net/Media/Video/+OPTIMUS+/SouthPawn++++.swfalso, note what i didnt do in this stuff:
you can make animations inside other animations by creating them inside a a Movie clip.
this way the granger can do a walking animation by itself WHILE moving this or that way., or smoke, tube split or anything can have an animation by itself what can be used multiple times.
also, you can easily import any vector formats to flash what can make graphics way better in some cases. with Illustrator, you can just Ctrl C+V.