ADDLOCAL=Feature_BackupEngine,Feature_BackupServer,Feature_ManagementTools /L*v %TEMP%\AltaroInstall.log
The issue here is attempting to use environment variables in the command line parameters. The command line parameters are normally evaluated by the Command Shell (as they were for your interactive install) prior to the execution of the msiexec.exe ... but when called via the WUA, [a] there is no command shell to evaluate the environment variables, and [b] the WUA sends the literal string direct to msiexec .. .msiexec doesn't know what to do with %TEMP%.
There's also a third point to be made here, but really academic only.... since the installation occurs in the context of the SYSTEM user, there is no %TEMP% folder available to write this logfile into.
The Windows Installer supports a default log destination when enabling logging, so I think rather than trying to force the logfile into a specific place, just specify the logfile name and let MSIEXEC put it where it wants to (or where it can, as the case may be).
An earlier conversation about the use of environment variables in the command line parameters is available at