This link will take you to a step by step guide to fixing the issue with someof the Saitek X52 pro buttons not working in Elite Dangerous. I followed this guide and all joystick and acceleration control buttons now work and are reconfigurable in Elite Dangerous.
About this video: When I first bought my Saitek X52 Pro I couldn’t get many of the buttons to work in Elite Dangerous, The game simply didn’t register many of the buttons on both the joystick and throttle control. I found a guide on an internetforum that allowed me to free up all of the buttons by changing some settings in the joystick profile software. Now all buttons on my Saitek X52 Pro are reconfigurable and useful! Hope this helps