The window can't be resized below a certain size, even though there does not seem to be any sensible reason for this. I use 1024x768 with a dual-line panel and can't see the entire window.
which version ?
The about window says this: 0.0.3svn (r) Xfce 4.4.0 I don't know if this Xfburn came with Xubuntu 6.06 or if it is from when I compiled Xfce 4.4 (the final release) from source.
*** This bug has been marked as a duplicate of bug 1857 ***