Hey,
This might be a wee bit late (by several years) but I needed something similar myself. I didn't get fast-forward and rewind going but I have play/pause/next/previous and display the track and time on the reader page. All I did was add:
<function id="doRight">this.bubble("doResume");</function>
<function id="doLeft">this.bubble("doSuspend");</function>
<function id="doDown">this.bubble("doGotoNextSong");</function>
<function id="doUp">this.bubble("doGotoPreviousSong");</function>
In the code block under here:
<kbookPage id="PAGE" left="0" right="0" top="0" bottom="30" href="x-id://bookData">
<code>
<!-- put new functions here! -->
And added:
<kbookLabel left="140" height="30" width="140" bottom="0" align="left" variable="SONG" />
<kbookLabel left="380" height="30" width="100" bottom="0" align="right" variable="SONG_TIME" />
just before </group> for PAGE_GROUP, then flashed as normal (see other forum posts).
I have to initiate the first song in the normal way then in the reader page I have control using the up/down/left/right keys (so history is gone - never used it myself).
Hope this helps & thanks to the guys that made the Universal Flasher!
John