I have both Visual Studio Express 2013, and Visual Studio Community 2015, installed "side by side" on my C: drive, which is running Windows 7, with the latest updates.

Both Visual Studio installs seem to play nicely together.
And every thing I've read says that this side by side install approach is perfectly kosher.

I also installed the free version of Visual Micro on the VS 2015 but have not used it for years.

Now I want to install Visual Studio Community 2019...again side by side...with the two older versions.

I also want to install the latest Visual Micro version on the VS Community 2019.

Will this new install of Visual Micro interfere with the Visual Micro installed on VS Community 2015?
Hopefully they each stand totally separate on their own.

Or could I uninstall unlicensed Visual Micro, and just go with the new version on VS 2019.
Would I be able to open old projects? 

Do I install the new Visual Micro from within the Visual Studio Community 2019 IDE?

I see Visual Micro is no longer free...so I want to pay for a single user license.
I assume I install what is a trial version...then pay for the license separately...get an emailed key...and unlock it?
Is that how it works?

Do Visual Micro updates flow to the Visual Micro install automatically?

Thanks for your attention...

Side by side is fine. Each IDE either has an extension installed or not. Each installation of VS is isolated and runs side by side.