Welcome to CD Freaks
Is there any reason you need the older driver over v1.2?
According to their page, a bug with DVBViewer showed up in v1.1, so if this is the problem you’re getting, you can try the workaround. It’s quite likely this workaround will still work fine if you’re using v1.2 drivers, so it’s worth a try.
The wordaround and v1.2 drivers can be downloaded here.
If you’re using DVB Viewer and still have an issue, go into the Setup menu -> Options, then Hardware tab and click ‘Scan Devices’. Then click ‘OK’ and hopefully it will have detected the new driver.