I'm sorry to hear about your bad experience, nswu1. Generally once they're installed and commissioned my customers complain of very few problems with Intellicenters, except "nobody has had to work on it for years so we forgot how."
During commissioning I do see a lot of problems and complaining, to which I use the simple analogy that DeviceNet is like swimming. Take a couple lessons, and you'll get along OK even when you're over your head. Jump in without learning how, and you're in trouble.
The 1788-EN2DN works almost exactly like the 1756-DNB bridge. The I/O connections are the same size, and the Status connection has the same format.
The principal gotcha I've seen with EN2DN is that it lacks an onboard display and manual settings for the DeviceNet node number and data rate. Insted you have to connect to the EN2DN over the Ethernet and set up the data rate (usually disable autobaud, too). You definitely want to learn the Status connection and provide a way for users to visualize it.
The DeviceNet Tag Generator Tool is a standalone tool included with RSNetworx for DeviceNet version 7 or version 8. You need the enhanced EDS files that are included with v7 and v8 to make this tool work.
What the DNet Tag Generator does is do a lot of the grunt work of integrating RSLogix 5000 and RSNetworx for DeviceNet. In RSLogix 5000, it creates User Defined Datatypes (UDTs) that match the data format of the devices in the RSNetworx project, creates tags with names that match the node numbers in the RSNetworx project, and then creates logic to copy data into and out of these tags based on where they are mapped in the DNet scanner's data table.
It works with any version of RSLogix 5000 later than v12, and works for any Logix-family DNet scanner, including 1756-DNB, 1769-SDN, 1788-DNBO, 1788-EN2DN and 1788-CN2DN.
If you've never worked with DNet at all, you won't see all the hard work that the DN.T.G.U. takes off your hands, but trust me it's a lot.