I guess problems would surface only when these are actually used, but from what I can see it looks pretty good.
I'm not entirely sure if its really needed, but I suppose when you have a constructor in there a destructor would be necessary as welll.

Also I noticed the default keyword, but without a value assigned to it. Why is that? And why use it at all? In the book Mastering Delph 5, the author says default values for published properties help reduce the dfm filesize and ultimately the exe filesize.