The core to a diagraming tool is to be able to detail/describe the entire data structure and data flow.
This tool is missing core database side functionality let alone being able to model/design/implement the entire application stack.
Currently the database is missing the support for the following functionality which is common across most SQL servers
*Database Roles
*Database Triggers
*Linked Databases
*Schema
*Functions
*Character Sets
Currently, although the database supports these items, they are not supported for diagraming
*Stored procedures
*Triggers
The above can all be easily added, I can provide the SQL needed to extract the above from most of the supported databases. I can also provide examples of how they can be displayed.
Most of the items can be supported with a group box - this would allow for diagraming a server, an instance/database within the server as well as any number of recursive schema as needed. Tables/views/procedures/triggers etc can be within a group or outside depending upon the layout/design needs.
A group box that holds a note as well would cover the needs for Triggers (describing the purpose of the trigger on the diagram while holding the source)
A group box that has input and output fields shown effectively showing an API style diagram approach.
Overall, the product is good but is missing enough features that it can not be used for it's purpose which is as a design/scripting/code versioning tool.