I did have when I initially put the gun together. I solved the problem by readjusting the latch so the rear of the magazine was positioned high enough to allow the bolt to clear the lips and still engage the cartridge.
The front of the magazine was a different problem as it was too low in the front to allow the cartridge to feed properly.
I made a "L" shaped piece similar to the one you showed in the original post and secured it with the original screw to provide a pivot point, this allowed the magazine to rotate up and back slightly using the latch cut as a pivot point on the magazine, with a spring between the upper portion of the block and trigger guard wall to provide tension and push the magazine up and back enough to allow the cartridge to line up with the feed ramp and lock into the release latch. Once this was done the magazine would slide in and latch.
I did run a ball end mill on the upper portion of the insert to match the rounded portion of the magazine and help hold in in position.
I also milled a few thousands off the bottom of the trigger guard as you might note in the photo, this did allow for a bit of room for the magazine to have room to move, not sure if it was necessary but did work.
This was a file and fit kind of exercise until things worked.
I hope this makes sense.
If you want I can take the adapter apart and send a photo.