1. If you have to re-install Bandicam because of hardware fault and so on, it's totally fine. They're not too strict on that policy.
2. I don't know anything about it myself, so we'll have to wait for Bandicam team.

I agree. I really want to see a third audio track into Bandicam, it would make the software even greater!

Change the video codec:
Under "Format" in the "Video" tab of Bandicam, click "Settings" and you will see the window to the right.
Change the video codec to something like "Motion JPEG" (where mine says "H.264 (NVIDIA CUDA)").

If you're on Windows 7, in the Sound settings (Video tab -> Under Record -> Settings), make sure that "Win7 Sound (WASAPI)" is chosen as one of the sound devices. This will record any sound that you can hear inside Windows 7.

The only restrictions on the unregistered version of Bandicam is the 10 minute time limit and the watermark, I'm pretty sure there aren't any other restrictions, although I'm not 100% sure.

Just to get this out of the way; Did you ever try to re-install Bandicam?

Also, have you tried to change output folders again after it stopped working this time?

Were you trying to save the files into a folder that might need administrative permissions? I know that Bandicam asks for admin permissions at launch, but that may still have been the issue.

I hope you mean seperately. Currently, you can choose where both are saved in the 'General' tab of Bandicam:

Guys I see that you're already thinking on adding some AMD optimizations (or OpenCL support) or even already implementing it, but still wanted to say that we - AMD users - really need this and really would appreciate it. Thanks. AMD support is already added, although it doesn't support the GPUs bei...

PayPal allows you to use your credit card without registering, I believe. I've used the same method here in Norway, with a Visa giftcard that uses the credit card number and such on PayPal, and succeeded with payments.