FYI, I just set three other sprites in a minimal program to vx of 0.17, 0.18 and 0.19. The sprite with velocity 0.17 doesn’t move most of the time, 0.18 goes at about a 1/5 of the speed of 0.19 in the simulator.
See https://makecode.com/_iaTaDhH8Ah28 for checking different low velocities. Works well with https://www.youtube.com/watch?v=Y4QbJRAWvRU playing in the background.