Open an elevated command prompt and type EXPAND -F:*.* xxx.cab C:\TEMP (where xxx.cab is the name of the CU file in cabinet format and C:\TEMP is the destination path), then unzip the 7z file attached above and type DISM /Online /Add-Package /PackagePath:C:\TEMP\Update.mum (if C:\TEMP is an example of the directory with all files extracted before).
18362.329.1.11 SSU/CU appeared on Catalog: https://forums.mydigitallife.net/threads/windows-10-hotfix-repository.57050/page-446#post-1544495
Added the new SSU too (previously in RP Ring, now on catalog): 18362.323.1.0 added to https://forums.mydigitallife.net/threads/windows-10-hotfix-repository.57050/page-446#post-1544495
It's not "very" needed, since they connected all .NET CUs together with CBS package name installing latest will auto-supersede previous ones
The Update: KB4517245-x64 & KB4517245-x86 > "It's Magic", It Converts Windows 10 > Version 1903 to Version 1909
No Flash update since June 2019? The latest version is still the same 2019-06 Security Update for Adobe Flash Player for Windows 10 Version 1903 for x64-based Systems (KB4503308) while other packages got/getting updates respectively each month.