Yes, it is totally fine.
We have customers that are located in many parts of the world, and often their website is not in English. That is no problem at all. Generally speaking the text link we would provide would be an English link, but it can be placed on any website you wish.
We have now deployed mxguarddog for five of our clients and use it on our own exchange server. Out of the box with no configuration it works brilliantly, the quarantine emails are great for the end user.
This system out performs many commercial spam filters we have sold in the past.
We are using MX Guarddog on a few different domains and love it. It has helped tremendously with keeping our time on useful tasks rather than sifting through SPAM.
It seems to just get better and better as well. I can’t say enough about how much we appreciate the service.