NOTE:

The TOpenGL component, in the process of linking into the OnDestroy
method of the form, disconnects FormDestroy in the designer, even if
you protect it with a test for csDesigning in ComponentState. The
workaround is always to re-connect the FormDestroy method manually
before each compile whether it looks like it needs re-connecting or
not.

An alternative is to remove the OnDestroy tie-in in the cOpenGL unit,
(in the Create constructor and the ShutDown method), and promote the
ShutDown method from private to public; then in the form unit always
create an OnClose handler in which you call OpenGL1.ShutDown(Sender).
(Use whatever name you let the TOpenGL object have.)
