Hi Tom,
I am one of the Product Managers on LiveCycle. Upgrade is one of my areas.
While the LiveCycle 7 upgrade to LiveCycle ES is relatively smooth, the upgrade from LiveCycle 6 to LiveCycle ES will require significantly more effort -- especially since you are using Workflow 6.2.
In LiveCycle 7, the Workflow engine was replaced with a Java based engine in order to give our customers more flexibility over platform choice. That engine came through Adobe through an acquisition. It was impossible to maintain compatibility from Workflow 6.2 to LiveCycle 7 (and hence to LiveCycle ES). You will have to rewrite your workflows in LiveCycle ES. The same types of operations are available in ES. But it will be a manual rewrite.
Forms that you created in LiveCycle 6 will render in LiveCycle ES as they did back in LiveCycle 6. However, if you need to edit your forms in Designer ES, you may need to edit the layout of the document in order to maintain its look and feel. Any script that you have in the forms will not need to be modified (except to work with the new Workflow engine). If you do have to edit your form in Designer ES, once you've edited the look and feel to work in ES, you won't have to change it again.
The other area is in the APIs. Many of the APIs that were present in LiveCycle 6 are present in LiveCycle 7. And as such, are included in the LiveCycle compatibility layer that is present in LiveCycle ES. The main exception is the toSimplePS() API. In LC7, it was documented that that API would go away in the next version of the product. So in ES, it did go away. There are other ways in LiveCycle ES to create a Postscript document.
The only way to get the compatibility layer in LiveCycle ES is to upgrade from LiveCycle 7. In the upcoming version of LiveCycle ES, we're adding flexibility to allow you to install the compatibility layer without having to formally upgrade from LC7.
We are working on a Technical Guide that describes best practices for upgrading from 7 to ES and from products previous to LiveCycle 7 to ES.
Thanks,
Mark