Hello. 
I compile a qt version qt 5.15.2 download from https://download.qt.io/official_releases/qt/5.15/5.15.2/single/ 

with visual studio community 2022. When I tried to add the library compiled

the qt Vs Tool catch a the following exception:

— qmake(18836): started D:\LAVORO\QT-EVERYWHERE-SRC-5.15.2\QTBASE\bin\qmake.exe
— qmake: Querying persistent properties
— qmake(18836): exit code 0 (89.77 msecs)

Value cannot be null.
Parameter name: path1

Stacktrace:
at System.IO.Path.Combine(String path1, String path2, String path3)
at QtVsTools.Core.QMakeConf..ctor(VersionInformation versionInfo, QMakeQuery qmakeQuery)
at QtVsTools.Core.VersionInformation.GetQMakeConfEntry(String entryName)
at QtVsTools.Options.QtVersionsPage.SaveSettingsToStorage() in C:\dev\source\qtlabs\vstools\QtVsTools.Package\Options\QtVersionsPage.cs:line 93