I strongly urge against it. The reason that Pokémon Liberated closed down was due to copyright issues. From what I understand, PUSA has been lenient lately about the way that we use their intellectual property. We have been promoting their product, so that hasn't been a big problem.
Pokémon Liberated's patches, on the other hand, interfere with PUSA's ability to make a profit. People could download the patches and play the TCG without buying the cards; therefore, PUSA loses money. From a business perspective, if you went through the time and trouble to make a product, then someone uses your idea without your permission, and it siphons off customers from you, you would want to prevent that from happening. That is why PUSA sent them a "cease and desist" letter, a letter basically telling them to shut their activities down before PUSA takes legal actions. PL's intentions were probably not malicious and they may not have realized that they were doing anything wrong. However, it is important to understand the law. In other words, "Ignorance of the law is no excuse for infringing it."