- At first, it seems odd that "RIDE ON THE LIGHT (HI GREAT MIX)" got a chart with Hell Charge Notes in copula; it's a very old song (it debuted in 5th Style in 2001), its composer Mr.T doesn't work for Konami anymore and now only does commission songs once in a while, and its charts don't really stand out (its SP Another and DP Another charts are rated 8 and 9, respectively, which to anyone at 9-dan or maybe even 8-dan translates to "who cares?"). However, the original "Ride on the Light" is a Keyboardmania song, and Keyboardmania is one of the first keysounded rhythm games to have hold notes. Conclusion: The new HCN chart is basically a tribute to Keyboardmania.
- ZZ was added to beatmania IIDX 22 PENDUAL because "ZZ" looks like the number 22.
- Similarly, the song Cookie Bouquets was added to Tricoro because the three characters from it's video represented the colors of Red, Yellow, and Blue, just like that of the theme of Tricoro.
- In PENDUAL's Future Phase, the year shown on the clock was always 2222. This persisted even into 2015. The Future Phase was a "Groundhog Day" Loop.