Rounding out the series I though I'd give a few examples of some 3rd party vendors in the AEC application integration software space. I've also added on some documents from the core vendors that I think are a good reference for non IT pros to learn from.
Morpheus Technology Group; They make a product called MTG Frameworks & an express version. Per my last post, while not Microsoft size, they have been focused on the AEC space for many years and have numerous customers. Being focused on AEC companies, they tend to have a good view of the enterprise apps like Oracle JDE, Oracle Primavera, and Meridian product lines.
Event 1 Software; For the 10+ years I've been in the AEC tech space, Event 1 seems to be the household brand around Sage/Timberline. They have a number of tools outside this arena as well, which fit into some of the other integration commentary in my post 1/6 and 2/6.
Oracle Primavera; Although not a specific middleware product, I like this Oracle article for general coverage of the integration process. There is also clear focus on Oracle scheduling and construction management products. You c an follow links from there to the partners section for various 3rd party product vendors focused on the Oracle line within the AEC Space.
While not intended to be a comprehensive list, hopefully that gets you going down the path, and you can google away with different related terms.