The core commands are DirectPlay(forum search DirectPlay), this is considered obsolete now by Microsoft according to Google results, so in Windows 10 you will need to enable it - Program features > Turn Windows features on/off > Legacy > DirectPlay(again according to Google, also disable antivirus/defender beforehand and a reboot needed afterwards). Perhaps this is behind what you are experiencing? Also make sure you're using correct dx9 for DBP, 9.0c June 2010 is what I have.
Win 7 Pro 64 bit SP1, AMD A4-5300 APU 3.4GHz, 8GB DDR3, NVidia GeForce GTX 750 1GB GDDR5, ASUS A55BM-E