Using EXCEL 2000, I want to create a 'Message Box', within a macro
routine, that will open when someone navigates to another worksheet
using 'navigation' buttons I've created on the worksheets.

I have no problem with the usual 'Fixed' messages e.g."Please check
Inputs before proceeding to next page", but I want a message that will
be specific to certain Inputs.
e.g. a perfect item is :-
1. Weight = 5 - 10Kg
2. Volume = 0.5 - 1.0 cubic meter

Now, if the end user makes entries to the worksheet, that when
calculated, show that the box weighs 7Kg and equals 1.2 cubic meters,
then I want a 'Message Box' to open stating that Weight is within
parameters ('OK') but Volume is 0.2 cubic meters outside the
parameters. Whatever Weight & Volume is calculated, I need to show on
the 'Message Box' when and by how much the parameters have been missed,
so in the above example Weight & Volume could each be a - value, +
value or 'OK' value. I also want each parameter to be shown on a
separate line on the 'Message Box', not one long line.

How do I set-up a 'Message Box' to place any EXCEL calculated variable
figures within the Message?

Note: the only option on the 'Message Box' for the end-user to click
will be 'OK', not anything else like 'Yes', 'No', 'Cancel', unless
someone can tell me how to display a 'Message Box' for, say 5 seconds,
before the macro routine continues (i.e. navigates to the next page)!!!