1. Installing SAP Solution Composer
You can get the SAP Solution Composer in http://www.sap.com/solutions/businessmaps/composer/index.epx
Start the installation program: 
This installation is easy, you can follow all program installation instructions.
When the program is installed, run the Solution Composer program.
2. Using Solution Composer
2.1 Business Map
The term “Business Map” refers to the entire contents Business Process and all graphical elements. In the design Business Map phase is important know how Business Process are modelled. The picture below shows a Business Map Structure: 
Each Activity we can identify KPI’s, Process Objetives, Products Used (SAP and non-SAP), Employee Roles, Classification, Process Ower, …
2.2 Using Solution Composer
On the first screen, is possible select one or more existing SAP Business Maps. If you want an specific Business Map, you can download newest versions on official SAP Solution Composer site. 
This example show an Value Added Chain with all your business scenario and the standard activities used to realize one process. 
2.3 Creating a new Business Map
Start with an existing Business Map (like a standard process used in a mySAP Customer Relationship Management). 
I my example, I will use only the Service Process to model my Business Area. So, I will delete all Process unused. Just click in Edit Flag. The Solution Composer shows this message: 
Just click in OK. This means you generate a new-copied Business Map (like a ABAP Z-COPY-PROGRAMS = ) ) The workspace shows an copy symbol of your Original Business Map. Check it out: 
I will drop the Marketing and Sales Process Category. Just click with right-button and select Remove Process Category. 
You can get any process supported in the Service Process Category and work with them. This picture shows how it’s possible view the SAP Standard features in a Service Order Quotation Process. 
Great Job.
It's going to be a god Web blog on SDN!
Regards,
Hailton
Further, it would be useful for readers to refer to the Solution Manager site:
http://www.sap.com/solutions/businessmaps/composer/index.epx
and download the virtual classroom session--its quite helpful
Best Regards!
-h
This Process Maps doesn't design an Reverse Bussiness Engeenier. You can design what you have or what you want in your Bussiness Enviroment.
The Solution Composer doesn't has the workflow funcionality. To use this funcionality there are some options:
1st) You can create workflows with ABAP Workbench. (Tradictional)
2nd) You can design the Business Process in SAP Solution Manager and use the funcionality BPMon (Business Process Monitor)
3rd) You can use the XI or PI (Process Interface, the new name of the SAP Solution), and create logs for each process control. These logs provides some info to undestand what is going on in your process.
Okay?
If some doubts don't hesitate.
Kind Regards
e-Zac!