To my knowledge, all the play/pause/stop/next/previous etc commands work, it will respond to queries asking for is playing/paused, is shuffle on/off, is random on/off and you can set shuffle/random from API.
I think I'll tidy it up a little and implement as much functionality as I can and then release the code so others can continue if there is anything missing,
I've written an external remotecontrol with optional php-class for winamp2.
I'm very interested in using it also for foobar2000, which is possible with your dll.
Have tested it and the basic functions are working.
But there are also functions which are not working now, mainly all my queries of current states for volume, panning, repeat and shuffle aren't answered.
Maybe it is possible that we can adapt both tools that they work pretty well together?
It would be really nice if you could implement a return for a query like 'send message 777' (which isn't known by winamp) that tells my tool that it is connected to your foobar_winamp_emulator,
Here's the link to my tool: http://www.nogajski.de/w2sp/
a list with supported message id's is here:http://www.nogajski.de/w2sp/binary.php#link4
(there are more id's that I use internally for quering informations, if you are interested I can send you)