Important (and nearly foolproof!) Steps to Running your PMDG product in Prepar3D v3

The good news is that Lockheed Martin has released Prepar3D v3 this week!  The bad news is that it leaves us with a couple of things we must fix to give you a trouble-free simulation in P3D v3.
While we work to sort out a few issues, we have four fool-proof steps to get you running your PMDG product quickly and effortlessly in Prepar3D v3.  These steps are listed here, and explained in detail a bit further down.  Please try them before you open a ticket, as we are confident that these steps will work for almost all users:
  1. Make certain your PMDG product is the only airplane that P3D loads into memory.
  2. Be sure to get the latest version of your PMDG product by downloading from your PMDG user account.
  3. Make certain you have all of the older simconnect versions installed.
  4. Turn off and ignore "Error Logging" in P3D.
Step 1: Make certain your PMDG product is the only airplane that P3D loads into memory:  We have had some users report back that parts of the Virtual Cockpit were not clickable, and/or that the displays in the airplane failed to initialize and load.  We have found that users can solve this by taking the simple step of making certain that their PMDG product is the ONLY aircraft that gets loaded into the P3D before flight. 
What To Do:  Launch Prepar3D v3 and navigate to the "Prepar3D Scenario Setup" menu.  On the lower right corner, next to the "OK" button, click on the "Show At Startup" box.  Now close and restart Prepar3D.  (This is important!)  When the sim launches again, you will be taken directly to the Scenario Setup menu, from where you can choose your flight.  This prevents P3D from launching another aircraft first, thus creating the problem you experienced earlier.
Background:  We have always recommended that when using a PMDG product, ours be the only aircraft that has been loaded in the simulator- but that was due largely to superstition that that the simulation platform didn't do a very good job of clearing out data from previously run aircraft.  Here we seem to have proof that "something goes amiss" so we are reinforcing that guidance in the short term.  In the long term, we are working on a solution and we will update you once we have one!
Step 2: Make certain you have the latest version of your PMDG product:  Using your PMDG product with Prepar3D v3 will require that you grab a new copy of the product installer from your account here at PMDG. 
What to Do:  Simply log in, go to your account history, and download a fresh copy.  We updated the installer so that it recognizes this new version of P3D.
Background:  Larger updates to the product lines are coming, but these were put together in order to simplify your installation process.
Step 3: If Steps 1 and 2 above do not solve your problem, you need to check your SimConnect installation:  We want to stress that 99% of users will have their problems solved by following Step 1 and Step 2. 
What to Do:  If you are still having trouble, please open the README file that came with your installer, and follow the steps outlined for installing the older versions of simconnect on your computer. 
Background:  Simconnect is a process that runs in the background and allows our products to talk to the simulator.  Simconnect is controlled by the sim platform, and occasionally it is handy to have the older versions present in case the product needs them.
Step 4: Turn Off and Ignore "Error Logging" in Prepar3D.  Lockheed Martin has reintroduced a horribly bugged process that first appeared in FSX back in 2006, "Error Logging."  This device was originally designed for developers to help identify problems during product development, but it was such a weak system that it proved to be largely useless as the information it provided was often misleading.
What to Do:  Launch Prepar3D v3, then go to OPTIONS, SETTINGS, GENERAL.  On the top left quadrant, you will see two check-boxes:  "Scenario Error Logging" and "Content Error Logging."  Uncheck both of these boxes.
Background:  While the information provided by this error logging process can prove useful to developers, the information often traps proper configurations and behaviors that are not actually errors, thus leading users to be confused as to whether there is a problem with their product.  For this reason we recommend turning the error logging off.  If you have concerns about your product, bring them to us here and we will help you to sort them out! (And yes, we do track these log files during development!)
If, after trying these three steps, you are still having trouble- open a ticket here and let us know.  We will do our best to get you up and running quickly!
The PMDG Support Team