Greg, are you sure you have not simply got a solution that is looking for a
problem to solve?

Sounds harsh, doesn't it? Unfortunately, life can be and usually is!

If you have you observed road works (in the UK) closely, you would not have
failed to notice that there are usually 3/4 people watching whilst 1/2 is
actually doing something. This communal activity goes by the name of 'team'
work or 'project' management! You seem to have denied the bystanders their
due by simply doing it; and now they do not want to know.

Where does this leave you? You have an application that has your
thinking/understanding embedded in it (unmodified by other points of view),
it is untested (you said managers don't want to know) and you have no way of
gauging its usability. Undoubtedly, you have neither a functional not user
specification. I would say, you have simply got a prototype.

To find out what you have got, one option is release the application into
the public domain without warranty: the objective is to quantify the takeup
rate and to assess the feedback you get in order to determine its commercial
viability.

Another option is to sell it as is. However, this is costly in that
marketing costs money and you would need to provide help desk type support
and possibly training also. You will also need to investigate and fix bugs
and manage future releases. All of this needs to happen whilst you are at
work. How will you manage?

So far, you have proved that you can analyse a problem and produce a package
solutiion; in the process, you have no doubt learnt a lot. I assume that you
use Excel daily as part of your work.

Unless you are of a brave disposition, I would suggest that you stop pushing
the application in the workplace. With a bit of luck, if the need for the
applicatioin is sufficient, the dynamics of the workplace will come looking
for it and when (if) this happens, have a strategy that yields some personal
dividends for you.

Good luck.