Executive Meddling: Gene Rayburn was distinctly told not to goof around as he did on Match Game, despite a goofy host being totally acceptable in a stunt-based show where the Prize Vault was full of silly stuff. It seems he wasn't given much of a pre-show briefing, either, as he stumbles around aimlessly more than a few times in the Prize Vault (some people have suggested that he originally thought he was going to host a revival of Break the Bank (1976); that's plausible, considering Kline & Friends was composed of defectors from Barry and Enright). Given the Prize Vault was timed (using the seconds the couple had earned in the front game), this was never a good thing when it happened.
The Prize Vault issue was partly fixed by stopping the clock when Gene needed to describe the chosen stunt. This change also helped the couples, as it allowed them to get set up for each stunt, increasing the odds of winning more cards and/or going to the Number Jumbler.
According to a recent biography, The Matchless Gene Rayburn, the reason he was picked to host was to have "star power", so stations would be more likely to pick it up, and hence wasn't treated very well (Kline apparently saw Rayburn as sort of a "means to an end"), and the reason they stopped the clock was so Rayburn couldn't make any jokes about the stunts in the Prize Vault.
Hey, It's That Sound!: Quite a few sound effects were recycled from Barry-Enright series- the Tic-Tac-Dough "category reveal" noise was used for the home viewer puzzle hint, the noise heard when the Number Jumbler stopped was previous used on The Joker's Wild as a "spin start" noise in the bonus round, and the "wrong code" noise was used as a "zero" noise in the bonus round of Play The Percentages.
Keep Circulating the Tapes: Except for a week of reruns in December 1985 (the first week of the series), no Rayburn episodes have been rerun, partly because he wanted it as such. About 48 of his 65 shows circulate among collectors, while some of Joe Farago's episodes were rerun by CBN Cable (what is currently ABC Family) in late 1986. (Ironically, Fox, who owned that network from 1998 to 2001, currently holds the rights to it, as the distributor, Blair Entertainment was a subsidiary of Storer Comuunications, which was absorbed into New World Communications, which was in turn acquired by Fox in 1997.)
Missing Episode: Gene's tenure. The most common explanation is because he was extremely dissatisfied with how he was treated by Kline & Friends and refused to talk about his experiences on Bank during interviews near the end of his life. As a result, you likely won't be seeing Rayburn's tenure again outside YouTube (unless Rayburn's death and Fox's acquisition of the Blair library have rendered it void).
Old Shame: Gene Rayburn was so unhappy with his hosting and the treatment he received on Bank that he declared an embargo on every episode he hosted.
Prop Recycling: It appears that the Numbler Jumbler monitor was recycled from the 1982 21 pilot's bonus game; Richard Kline was also involved in that.