Realfun 3

What does the CPU meter indicate? Is each block 12.5% CPU time? Is it just for generating the audio stuff or also the waveform visualization?

It's a basic idle time counter, which includes also the time required to draw the waveform visualizations. These visualizations are actually quite demanding, almost 1 block per channel IIRC. It is mostly indicative how busy the R800 is and is not an indication on what the CPU load is for the final in-game (z80) re-player. In the editor everything is calculated on the fly, in the re-player everything will be pre-computed.
Still, with all the waveform updates going on, it will have a 1 int peak load up to ~20% of z80 (on 60hz) and 4 int peak load average of ~16% (considering SCC+ with PSG). A few post back I posted an re-player CPU load overview for a couple of songs.

So, last couple of months I have implemented isr sample playback in the re-player (and .r3m to re-player format converter). For those who are interested in the z80 re-player, you can get it here: realfun3_rom_replayer_v051
Still plenty of (little) things to be done. But in case you are thinking about using realfun 3 music in your game, this will give you something to work with already.
Also I covered another song: End_of_the_dark
Enjoy!

I think this should go in the news with a link to the player files.