Yes! It *IS* sweet!! I must admit, I had to turn a few stones, to get it going.
Using the supplied XML generator did me little good, so I edited it by hand, using an exsisting Playlist.xml file.
Mostly it was trial and error. I was only interrested in streaming a few of my Reason tracks, so I chose mid sized player. (It looks way better than the CD-Player.) Here's what I did:

I created a folder in my homepage, a chose to call it 'Stream'.
In that folder I uploaded the folowing files:
'_pfs.swf', 'av_aquaplayer.html', and 'av_aquaplayer.swf'.
I created a folder in 'Stream', and called it 'media'.
In that folder, I uploaded my mp3s, and the customized Playlist.xml. IMPORTANT! The Playlist.xml had to be named 'onlyAudio_playlist.xml' to work. I later found out why, but the easies right now is to just use the name 'onlyAudio_playlist.xml' as playlist.xml name for when choosing to use the av_aquaplayer.html/av_aquaplayer.swf skin. Then.. And now it gets trickey.. I tried, (again, trial and error,) copy/paste'n the bits and pieces that I needed from 'onlyAudio_playlist.xml''s entry (that was streamed with no problems, when I used 'onlyAudio_playlist.xml' unmodified,) instead of the entries I had made using the 'XML Generator'.

FYI, it was this entry:

<PLAYLIST name="MP3 Audio" author="FODOR" Tr_Folder="" defaultKbps="128Kbps" defaultFolder="" Xtension=".mp3" BGproperties="" offline="">
<URL Url="http://fodor.liane.net" Label="Flash AV Player Home" Target="_blank"/>
<KBPS Kbps_1="" Kbps_2="" Kbps_3=""/>
<TRACK name="Les longs solos d'amour" img="" Url="http://fodor.free.fr/flash_AV_players/AV_players_folder/media/mp3/Les_longs_solos_d'amour.mp3"/>
</PLAYLIST>

Off course I tried using the the developers URL first: (fodor.free.fr etc.)
And presto. After supplying the URLs to my own tracks, it worked.

So.. It's a bit of a hazzle to set up. At least first time. But after it's set up, it's pure bliss!!

I can only recommend this streaming solution. Free and beautyfull!