Continuing the discussion from SpectraLayers 10.0.20 Maintenance Update:
Tried to download this update, got “Installation failed due to an unknown error” dialog in Download Assistant following download, suggested I manually install by double-clicking the installer file, but when found, it has an .sda-download extension after the .exe. Just remove this to run the installer… in case anyone else runs into this error. Perhaps this was why the install failed because the Download Assistant couldn’t run the file it created!