I've tried to crack this with gdb, but failed so far.
Latest changes in svn tree seem to have fixed it, whatever it was.
I have imported whole tree into an empty project, saved it, closed it and opened itd. Several times, without failure.
It seems that it is working now. It is slooooow as molasses, but it works.
BTW: Maybe endless object creation and destruction in C++ isn't such good idea after all ?
Same thing, written in decent C would simply fly...