I'm sorry that you're still experiencing a few problems with this program, let's see if we can resolve this for you.
PF3 doesn't need to be running for the program to try starting up (it just needs the correct library) - at the time we were trying to get it running.
However, PF3 needs to be connected to FS for PF3 WEB Display to work - the PF3 Display port isn't active until PF3 is running and connected.
So firstly, is the original PF3 Display application working with your configuration?
Assuming that the answer is 'Yes', please can you try connecting PF3 to FS before you start PF3 WEB Display - it tries 5 times at 5 second intervals.
(What I do is set-up FS for a free flight, load any flight plan into PF3 and connect it, then start WEB Display - I find that the quickest way to check)
If that doesn't work, please can you try the following with PF3 running and connected to FS:
Type 'Powershell' in the Windows search box (bottom left with Windows 10), and select 'Run as Administrator' for Windows Powershell.
Enter the following command (exactly, upper and lower case are important) at the command prompt and post the screenshot back here:
Get-NetTCPConnection -LocalPort 1010
*Edit* Actually, if standard PF3 Display is working, please can you do the above while PF3 Display is running and with PF3 connected to FS.