I am using webMethods version 8.0.1.

As per my understanding, creating process model in the Designer. When you build the process model, Process package will be created and the respective process model is enabled and the details will be stored in the Database. MWS fetch the data from the database and display it in MWS screen.

Do we require any step or settings between Designer and MWS other than compilation?

As my knowledge we configure process Audit Database is IS JDBC pool setting and for process model development we need to connect
with these database only and this is via IS server.
So In process development we need to set IS server in Process Audit Databse from Designer Preferences.
And mws fatches data from these dataBase.
So I think we no need to connect MWS from Designer for process Development.

Lets see what others say.

Connectivity to MWS is only needed if MWS assets are deployed, e.g. Tasks or Portlets. For processmodels without tasks no connection is needed.

1. Configure Integration Server (via IS admin - JDBC Pool) to connect to Process Audit database

Configure Designer
2. Windows > Preferences > Software AG > Integration Servers
3. Windows > Preferences > Software AG > Process Development > Process Audit database
4. Windows > Preferences > Software AG > Service Development > Package Navigator (if you want to see generated flow services, uncheck 'Hide generated flow services)

As lance explained, you need to configure ‘Task engine’ only if CAF tasks are there in your process model.

-Senthil