You're not talking about using a proprietary program to replace it. You're
talking about obtaining a copy of something by running a proprietary program.
The only possible analog I can think of is doing so with the intent of
sharing copies of the data with others illegally; in that case, you are
helping others avoid making a sacrifice you made. But as far as I can tell,
you aren't doing that. Instead, what you have done is told other people to
run a proprietary program to get a gratis copy of this game data legally.
What's more, this isn't even the only way to legally get a copy. Another
legal way, which doesn't require running any proprietary program, is to
simply buy a CD. I looked online; I see used copies of the Windows CD for
$10.
So let's recap. You're suggesting to other people that they should jump at an
amazing opportunity to save $10 by giving up their freedom, and that it's OK
because it's only a "one-time usage". I'm sorry, but I can't see any possible
way to justify this. What you are doing is steering people toward proprietary
software, and frankly, this doesn't belong on the Trisquel users forum.