For Jumper (original version) and La-Mulana (original retro version), it seems that DXGL gives only half the frames, which results in an important slowdown. This occurs using default DXGL settings. The problem has been there since several versions if I remember correctly, but it could be a regression indeed. This has been discussed in https://forum.dxgl.info/viewtopic.php?p=921#p921