The changes are there is no ADF Create Form in TP4 ( See Steve Muench quote), to solve this drag the right create operation of the viewobject from the datacontrol to the taskflow. A method call is created, make sure this method call runs before the page is loaded and the page is now in insert mode.
Steve Muench quotes "Notice that in TP4 there is no longer an "ADF Create Form" and that we're encouraging you to create a create form using a method activity that declaratively invokes the create operation, then forwards to a page with a regular ADF Form on it. This is due to the numerous confusions that have always surrounded the ADF "invokeAction" now that we have a visual, declarative mechanism to model this type of initialization activity, we will prefer users adopting that. Also, notice that the page definition for the method activity has the new "SkipValidation" property set to true."
Andrejus made a create sample how to use a lov when the form is in create mode. If you don't do this you get validation errors and the lov is empty.
A other issue is that the Commit operation fails with a table, you get a null pointer exception. This is bug in the JSF 1.2 reference implementation's validator tag (issue# 641): This issue is fixed in JSF 1.2_05. The TP4 release still uses JSF 1.2_04 that has this bug. The workaround to comment out the
In the datacontrol there is a bug
In TP3 you could reference to a valuebinding of a other pagedef (Task Flow memory scope), this fails in TP4 but there there is a workaround you can update the DataBindings.cpx file with the right pagedef id. At the pageMap remove the package name part of the usageId attribute and at the pageDefinitionUsages element remove also the package name part of id attribute. Now everything works again.
If you know other TP4 issues let me know and please update the oracle wiki yourself