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LiteOn provides the latest versions of its firmware on its website’s download section. From their main page, click on the ‘HDD+DVD Recorder Series’ thumbnail at the bottom of the screen and on the screen that appears, click the ‘Download’ tab. Look for the ‘LVW-5045’ firmware drop-down list and click the version for the country / region you are in. This presents a screen with with the download link as well as steps on how to go about the firmware update process. Unlike some other models such as the 5005, you don’t need to enter the serial number.
Here is a direct link to the firmware selection page:
To answer this question, I’ve decided to put the latest firmware on my LVW-5045 (203-UK). Unfortunately, with this latest firmware I can confirm that it is not possible to watch a DVD or any previous recordings while a recording is currently taking place.
However, it is possible to watch the current recording taking place from an earlier point, just like with time-shifting. To do this, press ‘Play’ as the recording is taking place and the LiteOn will begin showing the current recording from the start. It is also possible to navigate back & forth within the recording up until a few seconds before the ‘live’ point. The live point can be reached by pressing ‘stop’ once.