UPDATE: I received a letter apologizing for the poor customer service and offering a short term unlocked beta version, but I had given up on the project and moved on, using iMovie instead so they sent a refund immediately.
I tried this application and it seemed to work well. It made a great video and music mix, but then I purchased the single copy for 99 cents wtih the watermark. And received nothing. I thought I made a mistake and the purchase did not go through, so I did it again. Still nothing. I wrote customer service and they promised to send an unlocked short term release but then they did not send it and did not follow up. I have sent two follow up emails and there has been no response from their support team despite their promise of quick service.
In their only response, they told me there was a finder window that comes up to save and so, thinking it must have been my mistake, I tried again - spending another 99 cents. No finder window came up. There is a button that says I already purchased this video, so I tried that. It repeatedly came back that there was a problem.
So, I guess maybe this works if you buy the full version but their offer to allow you to buy one video at a time as needed is worthless. It does not work. All you do is waste your money and you get nothing - not one thing.