Generally, I do the RIT endings manually. It only takes a few minutes and lets you control it precisely.

I add a couple of new measures to the end. Shut off the canned ending or add enough measures so your hold fades completely. I tend to add 8 measures that will get edited out later in the DAW

I take the last 4 measures and change the number of beats from 4 to 2. In the first one, I set a new tempo less than the song tempo.. For example if the song is 120, you would set the first 2 beat measure to 112bpm. The next one gets set to 102bpm, the third one gets set to 90bpm, and the fourth to 78bpm. Set the very last measure in your song to any tempo but do a HOLD on that chord. If the drums play, you can silence them in one of several ways. You can use the D.pgb which exempts the piano, guitar, and bass letting them ring. You could also simply ignore the drums and export the files to a DAW and silence/edit them in the DAW. I use the second method all the time. Most of the time the dot following the chord works and sometimes I have to edit it in the DAW.

Regarding the tempos I used in the example..... you will probably have to adjust them to fit by playing it several times editing the tempos as needed. I find that using 8 beats divided across 4 measures allows the tempo to RIT without sounding like it's taking steps down. You want it to be as natural sounding as possible. It depends on how drastically you want the RIT to be. You can do it over a longer time using 6 or even 8 two beat measures but I find that 8 beats total often work extremely well and sound natural.

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