Hi Basj!
Thank you for the reply! 
I apologize for the data gap 
A. I have the following Stardock apps still installed:
1. Deskscapes
2. Fences 3
3. Groupy
4. Object desktop
5. I had Start 10 installed as well, but Start 10 was uninstalled either automatically or by me after a prompt to do so, when I first installed Start 11.
B. My Computer & OS configuration are as follows:
1. I have a desktop machine just over a year old.
- HP Pavilion Desktop - TP01-1127c // Memory Size 32768 MB RAM
- BIOS Date 03/19/2021 // BIOS Revision F.31
- Processor (1): Intel(R) Core(TM) i5-10400F CPU @ 2.90GHz //Current Processor Speed 2871 MHz
- Memory 2x DIMM2 (32gb total) // Manufacturer Crucial, Serial Number E43FABAA, each DIMM = 16384 MB , 2667 MHz, DDR4 // Synchronous array
2. My MS Windows version is a preview version of Windows 11
- Microsoft Windows [Version 10.0.22000.160]
- Install build: 22000.160 co_release
- I am in the Windows Insider Program Beta Track, and this is latest beta track version --perhaps several days old.
Comment: After the initial install, when I enabled Start 11, and clicked the start menu, I could see the pause -literally for seconds before showing the native Win11 for most cases (finally got it to show Start 11 but only ephemerally, one view and then reverted! (This computer rarely has to pause in any normal activities like opening windows, pressing start, opening explorer or apps; so watching this pause was disconcerting.)
Then did the re-installs and tweaking each and every function of Start11.
I must note that prior to finding & installing Start11, I had tried the Regedit hack of adding a DWord (32-bit value) called: ShowClassicMode (Value Data =1) to the HKEY-LOCAL_MACHINE\SSOFTWARE\MICROSOFT\WINDOWS\Current\Version\Explorer\Advanced Part of Window 11 Registry.
That did not work, so I repeated the process and added the DWord value as a 64-bit entry (I am running 64bit Windows), but that did not work either. I subsequently read somewhere that this change was nullified in the latest version of Win11 -the 160 co_release. I deleted these entries from the Registry and rebooted prior to the install of Start11.
OK, I appreciate any insights you might offer and thank you for your help in advance!

Mark
P.S. I don't think my AV program is interfering -it is McAfee All Access and it did not interfere with Start10, plus I did not get a warning about it. I may disable and retry running the Start11 with the start button (I can get windows key to trigger Start11 now). Thanks in advance!