Out of my curiosity, I too deployed XADisk.rar on JBoss 5.1.0/Java5. The deployment revealed a few changes in ra.xml, which were not caught by Glassfish (Glassfish didn't complain those things). Then, it goes good and I also wrote a simple test-case (managed application) to give a sanity check with JBoss.
I have now uploaded the modified .rar, which you can download and deploy on to GlassFish, JBoss (and any other J2EE server) : Updated XADisk.rar
Now, about your question on connection-factory, I have used the Admin Console (/admin-console) to create a connection-factory for XADisk. It works fine. The links I followed were -
admin-console --> Resources --> Connection Factories --> Tx ConnectionFactories --> Add a new Resource --> Select Resource Template (XA Connection Factory) --> from here, you only need to give these details:
JNDI Name (eg "xadiskcf"), RAR Name ("XADisk.rar" if you haven't renamed after downloading), Connection Definition (org.xadisk.connector.ConnectionFactory). I haven't altered/set other options; so may not comment on them.
Once connection factory gets created, the following sample code in my servlet goes successfully:
On your other question. Yes, in the guide, "jca/xadiskcf" was used to refer to such a connection-factory only.
I hope that should help. Let me know if there are any queries.