I have made many grid flights by using DIY mission planner.
If you look at the text file of a mission planner grid flight file you will see that they are very similar. All you need from the MP file is the waypoint data. I use "Excel" to make it easy to pull the waypoints out of the MP file and place them in AQ mission Excel file. Once you learn how to do it, it only takes a few minutes.
The one trick you need to learn is to "select all" to highlight both an AQ and the modified file to make sure they both have the exact same format. The first line in the file is very important to have the same format.
Larry