fin, it looks like it should work, so I am guessing the problem is in naming and location of the fields. You can help yourself see where the problem is by putting a little text into your test template. For example:
- Book entry is: {book-entry}
- Comment body is: {comment_body}
This will let you see whether you’re actually listing entries, and then whether the relationships are working, even if the field name isn’t quite right.
comment_body needs to be a field in the related ‘comments’ channel, or whatever it is named.
Here’s a similar example I just put up for another support posting: http://ellislab.com/forums/viewreply/859042/.
You can see there how no_related_entries may be useful to you as well.
fin, I think that once you have the details accurately so that this example works, then it will be easier to think clearly about the full arrangement you propose. I think it probably depends on how many books would be in review, as far as whether or when you need Playa.
There’s a scale factor involved, as far as how many books a reader has to sort through, to set the relation to the one they want to comment on. But you will see that, once you get this example operating.
Regards,
Clive