It sounds worse than it is. Here is a quote from ABC News, "“The subcommittee found that in regard to two projects, Mr. Gingrich engaged in activity involving 501(c)(3) organizations that was substantially motivated by partisan, political goals,” the report says. “The subcommittee also found that Mr. Gingrich provided the committee with material information about one of those projects that was inaccurate, incomplete and unreliable.”"
So basically, he was using funds for organizations he was involved with that were supposed to be non-partisan, but used the money for partisan purposes. Also, since it was supposed to be non-partisan, special tax breaks were involved, when they really shouldn't have been. At least, that is my understanding of what occurred. He was fined 300,000 dollars and resigned from his Speaker position.