The only way to install the previous versions without setup.exe**** (and being unkillable) was to install from a Full version of the setup rather than the web version.
Is there a full version to download as previously Has there been any correspondence with Sunbelt to try and fix the problem
"Installation To start the installation process, you will need to run the download file; this will initiate the installation of the .NET Framework 3.0 Release Candidate; If you have troubles with the download manager, you can download the entire package for x86 or for x64 which are both .EXE files."