I suggest you take a look at Mailbox View, which can be downloaded from Cool Solutions here.
Mailbox View displays a list of messages in a Formativ Portal, where each item includes basic message properties like Subject, Date and From. In particular, subroutine StoreMessageInList in the source code obtains the relevant properties of a message.
You will find there is a plentiful supply of example Formativ applets – ready to run solutions – at Cool Solutions and at Formativ Applet Central. These examples are very useful for a Formativ beginner to study.
In addition, you can study the complete list of message properties and methods at the GroupWise Object API reference here. Note: this is the base Message object; there are specializations (with additional properties & methods) for message types like Mail and Appointment.
Hope this helps.