No... that wouldn't be the problem at all. The camera may capture to .AVI files, but if you're streaming, then the internal file format is completely irrelevant because you're going to be looking at the output signal, either HDMI, or Component (RGB), which is an electrical signal, not a file format. So, you need to connect either an HDMI cable from your camera to the RGC HD Pro, or an RGB cable from your camera to the RGC HD Pro. Is that what you're doing?
Or are you trying to copy the files from your camera to your computer first, and then expecting to do something to stream those? That won't work. You need to input a video signal into the hardware (RGC HD Pro) and then you can stream from that.
As for capturing, you wouldn't use the RGC HD Pro for that, you would simply connect your camera to your computer, probably using a USB cable, and then copy the video files directly to your HD, and then edit those as desired. "Capturing" through the RGC HD Pro would involve conversions that you don't need to do.
So, I think you need to clear up for us exactly what you're trying to do.