I had Popcorn 4 installed on an iMac running Snow Leopard which was then upgraded to Lion and then Mountain Lion. At no time did I get anything other than perfect behaviour from Popcorn 4. I now have a late-2012 model iMac running Mountain Lion 10.8.3. It does not have any optical drive so I have not bothered installing Popcorn 4 on this but decided to give it a try. As far as I can determine, Popcorn 4 works perfectly, even with an external DVD drive. So, although Roxio's web site says that Popcorn 4 is not supported on Mountain Lion, it nevertheless seems to work. It is worth persevering with trying to get it to work before buying something new and more expensive. Incidentally, when I ran Popcorn 4 just now, I got a message saying that a new version was available (4.0.2 I believe).
Thank you for your suggestion to continue with Popcorn. In fact I do have 4.0.2 and until my upgrading to OS 10.8.3 it worked perfectly. What happened was that I was able to burn a DVD, using Popcorn, but it took three goes to write one DVD.
I now believe that the problem was not Popcorn but the upgrade to Lion. It seems that my computer goes into the sleep mode when there is no activity and it does not recognise burning a DVD as activity. (This is my theory so don't bet your house on it. I've changed the frequency of the screen saver change and the desk top from fifteen minutes to one hour and I hope that this will solve the problem.
I do thank you because I would not have thought to persist with Popcorn had you not put the argument so cogently.
Given the number of threads reporting sleep issues after upgrading to Mountain Lion, your explanation sounds at least plausible. One hour might not be enough so I would suggest extending this if you still get a problem writing a DVD. Just as an aside, I assume that you are NOT using an external DVD drive - I understand that such devices, if they are USB powered, can occasionally fail to complete the write process if the USB port to which they are connected lacks enough power. However, if you have had no problems until upgrading to Mountain Lion, this would appear to be unlikely in your case. As another Popcorn 4 user with 10.8.3, I would be interested to hear if extending the active period solves your problem.
Many thanks for your suggestion. I will extend the period between the sleep mode (I have just extended it to one day. But I think this might be too long). Yesterday I burnt two DVDs and had no trouble but I was continuously keeping the screen live. I will let you know if the problem is resolved when I next have a film to burn. It might be a few days.
Concerning an external DVD drive, I don't use one.
I recently posted a problem concerning Lion and Popcorn 4. Since upgrading to Lion Popcorn 4 did not work properly, or so it seemed. Since upgrading to Lion I was unable to burn a DVD. Roxio told me that Popcorn 4 did not support Lion. However, members of this group assured me that Popcorn and Lion did work together.
Eventually, after two lengthy phone conversations with Apple, the problem was cured. The problem was that Airport Utility kept interrupting the burning process by advising me that my Airport Base Stations were active. Apple eventually solved the problem and stopped the Airport Utility from continuously appearing.
I am grateful for the support I received from the Community and hope the that information about the resolution of the problem might be of interest to the group.