[Building Sakai] Advice re New Content Type

[Marc Savitsky]

Hi,
I need to create a new content type, so that I can write some custom 
code in the create and amend functions, otherwise the new type will be 
very similar to a FolderType.

All was going well, except I can't see the new type in the resources 
tool because of:

org.sakaiproject.entity.api.serialize.EntityParseException: Data block 
is not of tye org.sakaiproject.content.types.folder
         at 
org.sakaiproject.content.impl.serialize.impl.Type1BaseContentCollectionSerializer.doParse(Type1BaseContentCollectionSerializer.java:324)

It seems that content collection types other than FolderType are 
discouraged.

Please could I have some advice as to the best way to code around this 
restriction.  My environment is sakai 2.8.

thanks
Marc Savitsky