I did an administrative install: msiexec /a setup.msi
This will make a admin-share which you then can update with the Service Pack 2.
Download the SP2-exefile. Run it with /admin and point to the admin-share. Then it will update the share with SP2. The you are good to go to install an updated CorelDraw-package.
I search long for the complete command line parameters of setup.exe and receive from corel support the file "CorelDRAW Graphics Suite X5 Deployment Guide.pdf".
That's what I use for deployed installations:
setup.exe" /qb /li "%TEMP%\CorelDrawInstall.log" USERNAME="<yourName>" SERIALNUMBER="<license-key>" CLIPARTSOURCEDIR="<network-share>" ADDLOCAL=Draw,PP,Capture,Filters,UseGuide,EN,DE,English,German