I assume your spacedesk is connected over WiFi network, is that correct?
Routers can cause lags and latency. Bypassing them always improves performance. Configure Windows PC or Android device as WiFi Access Point (Hotspot) and connect to it before connecting spacedesk.
USB Tethering achieves the same result.
Please check the chapter “Performance Tuning” in the instruction manual: https://spacedesk.net/user-manual
By the way, does the BSOD upon settings OFF still happening on latest spacedesk version 1.0.8?