How to view the Development Engine logs?

I was build an application that has connectors with external database, in the studio everything works normally, however now that I imported the * .bar file to an error development engine on the first connector, so I need to see the development engine logs to find the error that may be occurring, have any way to view the development engine logs in your interface?

Bonita Eclipse Marketplace

Dear All
I want to get knowledge of bonita source code, hence, I want to open Bonita BPM Eclipse Marketplace from "http://marketplace.eclipse.org/content/bonita-bpm#group-details" link. which version of java SDK and eclipse IDE do I need? should I set any configuration in IDE before run it?
I want to get information about Bonita engine and how it handles the tasks that assigned to each user in Process?