Fun fact: the rules of a board game are not protected intellectual property. As long as you don't:

• copy a particular written account of the rules,
• any graphics or branding content from the original game,
• violate the trademark by creating something that could reasonably be mistaken for the original,

I believe it's not a violation. If you believe otherwise, I'm definitely interested in hearing about it.

Realistically though, I wrote this so I could play with my friends, after discovering the otherwise-excellent isc.ro didn't seem to support more than two players. I'm unlikely to make a major commercial enterprise out of it.