Hal,

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I have yet to make it do anything sensible if the initialization is interrupted. A couple of ideas re that:  - What does the DOS Fractint do in that situation?

I will have to look.

 - Could that section be made non-interruptible?

If RAM is being used, it is.  But, the RAM initialization is so fast, you don't notice it.  For using the hard disk, you really do want to be able to stop it if you decide you have made a mistake.

 - Would it be reasonable to have the initialization started again from its beginning.  (I've no idea if this is practical.)

Ideally, yes.  But currently what happens is that the image starts to generate.  The code should send you back to the video mode selection screen, but doesn't.

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There are still some screen issues with switching disk video modes Is this referring to the smaller screen sizes/video modes showing the text almost too small to read?

It is not that the text is too small.  The logic mistakenly thinks it has a graphics screen instead of a text screen. Jonathan