Update extra model path config docs (#275)

Author: comfyui-wiki

snippets/install/add-external-models.mdx

@@ -85,6 +85,10 @@ my_custom_config:
     controlnet: controlnet
 ```
 
+<Warning>
+  For the desktop version, please add the configuration to the existing configuration path without overwriting the path configuration generated during installation. Please back up the corresponding file before modification, so that you can restore it when you make a mistake.
+</Warning>
+
 Or you can refer to the default [extra_model_paths.yaml.example](https://github.com/comfyanonymous/ComfyUI/blob/master/extra_model_paths.yaml.example) for more configuration options. After saving, you need to **restart ComfyUI** for the changes to take effect.
 
 Below is the original config example:
@@ -158,3 +162,18 @@ a111:
     hypernetworks: models/hypernetworks
     controlnet: models/ControlNet
 ```
+
+### Add Extra Custom Nodes Path
+
+Besides adding external models, you can also add custom nodes paths that are not in the default path of ComfyUI
+
+<Tip>
+  Please note that this will not change the default installation path of custom nodes, but will add an extra path search when starting ComfyUI. You still need to complete the installation of custom node dependencies in the corresponding environment to ensure the integrity of the running environment.
+</Tip>
+
+Below is a simple configuration example (MacOS), please modify it according to your actual situation and add it to the corresponding configuration file, save it and restart ComfyUI for the changes to take effect:
+
+```yaml
+my_custom_nodes:
+  custom_nodes: /Users/your_username/Documents/extra_custom_nodes
+```

snippets/zh/install/add-external-models.mdx

@@ -83,6 +83,10 @@ my_custom_config:
     controlnet: controlnet
 ```
 
+<Warning>
+  对于桌面版，请在原有配置路径下新增配置，而不覆盖掉安装过程中自动生成的路径配置，请在修改前备份对应的文件，这样在你配置错误时可以及时恢复
+</Warning>
+
 或者你也可以参考默认的 [extra_model_paths.yaml.example](https://github.com/comfyanonymous/ComfyUI/blob/master/extra_model_paths.yaml.example) 来配置，保存之后， 需要 **重启 ComfyUI** 才能生效。
 
 下面是完整的原始的配置配置示例:
@@ -136,4 +140,19 @@ a111:
 #    gligen: models/gligen
 #    custom_nodes: path/custom_nodes
 
+```
+
+### 添加额外自定义节点路径
+
+除了添加外部模型之外，你同样可以添加不在 ComfyUI 默认路径下的自定义节点路径
+
+<Tip>
+  请注意，这并不会改变自定义节点的默认安装路径，只是在启动 ComfyUI 时会增加额外的路径搜索，你仍旧需要在对应的环境中完成自定义节点的依赖的安装，来保证其运行环境的完整性。
+</Tip>
+
+下面是一个简单的配置示例（Mac 系统），请根据你的实际情况进行修改，并新增到对应的配置文件中，保存后需要 **重启 ComfyUI** 才能生效:
+
+```yaml
+my_custom_nodes:
+  custom_nodes: /Users/your_username/Documents/extra_custom_nodes
 ```