Disclaimer: I am no coder and had no hand in developing any of the applications/tools listed below in the prerequisites, so please don't hold me accountable for any random problems that may arise. This thread seems to indicate some people are having problems burning non-LAME encoded MP3s, but since I don't use MP3s, I cannot confirm.
Prerequisites:
1. The latest version of Xlobby.
2. Foobar2000 v0.9.1 and the new Foobar plugin. (Burning a playlist from within Xlobby can be done with older versions of Foobar [in fact it's even easier], for which I can write a separate guide if there's interest [the event commands are slightly different]).
3. The CD Burning Component for Foobar (place the .dll in Program Files > Foobar 2000 > Components folder).
4. Nero Burning ROM (v6.x or above should be adequate)
5. Whatever Nero Plugin necessary to burn your archived files (mp3, flac, etc.)
Basically you just queue a CD, create your own queue, or load a playlist and then press a button assigned the following event (you will need to adjust the text in red if you installed foobar somewhere other than C:\Program Files). The burn command will be sent to your default burner. If you want to adjust the default options, load Foobar outside of Xlobby, create and highlight a dummy playlist and right click > Convert > Write Audio CD... and make adjustments in the pop-up window. Cancel the burn, but these changes should "stick" for next time your burn from within Xlobby.
I'm in the process of trying to figure out a way to calculate total playlist time, so that you can tell if your playlist will fit on a CD or not, but at the moment at least it provides a handy way to make audio backups of stuff in your archive. I'm also not certain at this point if it's possible to adjust length of gaps between tracks.
Hope this proves helpful for somebody.
<event>
<name>burn playlist</name>
<commands>
<command>
<type>music</type>
<execute>player load playlist</execute>
</command>
<command>
<type>os</type>
<execute>execute file</execute>
<parameter>C:\Program Files\foobar2000\foobar2000.exe</parameter>
<parameter>/command:"Select all"</parameter>
<parameter></parameter>
<parameter></parameter>
</command>
<command>
<type>timer</type>
<execute>wait</execute>
<parameter>20</parameter>
</command>
<command>
<type>os</type>
<execute>execute file</execute>
<parameter>C:\Program Files\foobar2000\foobar2000.exe</parameter>
<parameter>/playlist_command:Convert/"Write Audio CD..."</parameter>
<parameter></parameter>
<parameter></parameter>
</command>
<command>
<type>timer</type>
<execute>wait</execute>
<parameter>1000</parameter>
</command>
<command>
<type>os</type>
<execute>send message</execute>
<parameter>#32770</parameter>
<parameter>Audio CD writer setup</parameter>
<parameter>WM_Command</parameter>
<parameter>1</parameter>
<parameter>787116</parameter>
</command>
</commands>
</event>