With AUTO_CURSEFORGE handle modpacks not allowed for distribution by author (#2059)

README.md

@@ -631,14 +631,14 @@ To manage a CurseForge modpack automatically with upgrade support, pinned or lat
 > ```shell
 > docker run ... -e "CF_API_KEY=\$11\$22\$33aaaaaaaaaaaaaaaaaaaaaaaaaa"
 > ```
-> You can use a `.env` file, in the same directory as your `docker-compose.yaml`, and define your API Key there to remove the need to escape the `$` in your API Key. The `.env` file is [loaded automatically by docker compose](https://docs.docker.com/compose/environment-variables/set-environment-variables/#substitute-with-an-env-file). 
 > 
-> *.env*
-> ```
-> CF_API_KEY=$11$22$33aaaaaaaaaaaaaaaaaaaaaaaaaa
+> To avoid exposing the API key, it is highly recommended to use a `.env` file, which is [loaded automatically by docker compose](https://docs.docker.com/compose/environment-variables/set-environment-variables/#substitute-with-an-env-file). `$`'s in the value still need to escaped with a second `$` and the variable needs to be referenced from the compose file, such as:
+> ```yaml
+> environment:
+>   CF_API_KEY: ${CF_API_KEY}
 > ```
 >
-> To use with `docker run` you need to specify the `.env` file
+> To use the equivalent with `docker run` you need to specify the `.env` file explicitly:
 > ```
 > docker run --env-file=.env itzg/minecraft-server
 > ```
@@ -664,6 +664,8 @@ For example:
 -e TYPE=AUTO_CURSEFORGE -e CF_SLUG=all-the-mods-8
 ```
 
+If the authors of the modpack have disallowed project distribution, then the desired **client** modpack zip will need to be manually downloaded and made available to the container. The path to that file must be passed to `CF_MODPACK_ZIP`.
+
 The latest file will be located and used by default, but if a specific version is desired you can use one of the following options. With any of these options **do not select a server file** -- they lack the required manifest and defeat the ability to consistently automate startup.
 
 - Use `CF_PAGE_URL`, but include the full URL to a specific file