Download testopia add-on from VBS web site. It is a zip file (vbs21-testopia.zip) with a virtual disk.
Shut down VBS by clicking inside VMWare window and then pressing Ctrl+Alt+Insert.
WARNING: It is important that VBS is shut down and not "hibernated", because you are going to change virtual hardware. Make sure there are no *.lck or *.vmss files in the VBS directory.
Unpack vbs21-testopia.zip in the VBS directory. File vbs21-testopia.vmdk must overwrite existing file with the same name.
Open VBS VM in VMWare Player or Workstation and start it. When VBS finishes loading, you should see freshly installed Testopia URL:
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