WIFITUNES  You can read, can't you ?

As explained there are technical reasons to not do it like you expect.

I'm not going to comment on this any more.

Take it, or leave it.  
(Version 0.9)

WIFITUNES  If you really want to change this number, find the file gettracklist.scpt in the wifiTune.prefPane bundle and change it in the line "if (count each file track of current playlist) is less than 500 then" to whatever you like.

But you will see that higher numbers are not practical.  
(Version 0.9)

WIFITUNES  It works like this:

When you select a playlist in wifitunes, the playlist is selected in iTunes. If iTunes was playing a song before selecting a playlist, it will play the current song from the now selected playlist. If iTunes wasn't playing, wifiTunes will check if the current song is playable.

In both cases, if the current song is not playable by iTunes, wifiTunes will return to the playlist selection.

In both cases, if the current song is playable, you can press the "arrow left" to get to the track list of the selected playlist.

Now if, and only if, your playlist is not longer than 500 tracks, it will be shown in the order iTunes will play the tracks. You can select a track and it will start playing. If your playlist is longer than 500 tracks you will see "too many tracks", that is A) because Apple Script, which is used to interface iTunes is a bit slow in getting the track list, and B) 500 tracks are allready way too many to scroll thru in mobile Safari.

That is why we plan to incorporate a track search in a future release.  
(Version 0.9)

WIFITUNES  As we mention at http://wifitunes.wordpress.com/limitations/ the list of track in the current playlist is limited to 500, cause it would take ages to scroll thru all the tracks with mobile Safari. If it is larger you see "too many tracks". The only usable way to select specific track would be an search feature, which is planned for a future release.  
(Version 0.9)

WIFITUNES  That's strange.

Have you tried to start playing a song manually and then start using wifiTunes?

If you still have problems please comment on our website http://wifitunes.wordpress.com/feedback-contact/ and provide any info you can (console log, etc.)  
(Version 0.9)