This may not be any help because I've been using Amapi Pro instead V7 and have forgotten if V7 has this tool. Apologies if it doesn't help... :(

MDC's way works for sure. The way I indicate below can be done while preserving the DG - no need to collapse it.

Here is how I fix that in A7pro: With your DG object selected, click the Tesselation tool which presents you with the tool bar shown above. Then click where the mouse is shown. You'll be presented with the info window which shows the Max Angle as 20 degrees. I change it to 10 which makes all of the DG smooth when importing directly into Carrara as an Amapi file.