Enable fall damage by RTB prefs or by advanced options. make sure your Blockland folder is not read only and is not being blocked by any security software. (eg. Firewall, antivirus) To solve the keys moving problem, stop your charecter in any position without moving him, minimize blockland. If your charecter moves, try to press the key that your charecter is moving to. (eg. Forward, press W).
This isnt tested and positives results aren't guaranted.