README.md in administrate-field-nested_has_many-1.3.0 vs README.md in administrate-field-nested_has_many-2.0.0

@@ -1,9 +1,25 @@
 # Administrate::Field::NestedHasMany
 
 A plugin for nested has_many forms in [Administrate].
 
+[Administrate]: https://github.com/thoughtbot/administrate
+
+## Compatibility
+
+This gem depends on Administrate APIs that may change over time. For this reason,
+some versions of this gem will be compatible only with some versions of Administrate.
+
+This is a table of known compatibilities. It is accurate to the best of our knowledge.
+Please let us know if you detect other incompatibilities:
+
+| `nested_has_many` | Administrate  |
+|-------------------|---------------|
+| v1.3.0            | up to v0.15   |
+| `#726d8gc`        | from v0.16    |
+| `master`          | up to v0.19.0 |
+
 ## Usage
 
 Add to your `Gemfile`:
 
 ```ruby
@@ -33,6 +49,27 @@
 for the `NestedHasMany` field.
 Otherwise, Administrate will try to render a field
 for the order's `:customer` attribute,
 which breaks the nested form logic.
 
-[Administrate]: https://github.com/thoughtbot/administrate
+## Troubleshooting
+
+### `undefined method 'new_record?' for nil:NilClass`
+
+This field assumes that your models are setup for nested assignment as per
+Rails conventions. For example, if you have a `Recipe` that
+`has_many :ingredients`, you would have something like this:
+
+```ruby
+class Recipe < ApplicationRecord
+  has_many :ingredients
+
+  accepts_nested_attributes_for(
+    :ingredients,
+    reject_if: :all_blank,
+    allow_destroy: true
+  )
+end
+```
+
+Specifically, you'll see this `new_record?` error if you forget the
+`accepts_nested_attributes_for` declaration.