I don’t have Reaper here, so I can’t look at the chart proper, but this might work as a temp filler until the Creators docs are online:

http://keepitfishy.com/d.php?5167e85a17ed5

It’s geared towards harmony upgrade authoring but has a crash course in general vocal authoring since that’s necessary.

Bends are charted with the lyric/syllable on the first note of the sequence, and then a new note on each pitch with a + as the lyric. Leave some space between each note as that is where the slide itself occurs (look at that doc for a screenshot visual).