more doc

README.md

@@ -44,7 +44,10 @@ like this (as **superuser**):
 # ./util/internet-sharing wlan0 eth0 start
 ```
 
-To make the changes persistent, consult your Linux distribution's documentation.
+To make the changes persistent, consult your Linux distribution's
+documentation. **Warning!** Sleep/hibernate and resume cycles might mess up
+networking -- in case of problems, such as broken outgoing connections,
+restart both networking and internet sharing.
 
 ## Testing ##
 
@@ -52,3 +55,16 @@ A CLI-based client script is available: `post_client.py`. See how to use it with
 ```
 $ python3 post_client.py -h
 ```
+
+## Caveats ##
+
+This lab is based on `python-openzwave-0.3.0b8`. Newer versions are not
+compatible with our app template, so, please avoid upgrading your
+installation!  Note also that the latest documenation differs with respect to
+our template in the following symbols ("old" is what we have; the list is not
+exhaustive, sorry):
+
+|old|new|
+|---|---|
+|`node.isReady`|`node.is_ready`|
+|`node.getNodeQueryStage`|`node.query_stage`|