Mind Cubes 16-20

Solution #16:
Yellow (from the right) - D5, L6, U1.

Green (from the left) - D1, follow the edge of the puzzle all the way around clockwise.

Orange (from the right) - L2, U1, L3.

Blue - Follow the remaining path.

Solution #17:
Purple - Shortest route possible.

Orange - Shortest route possible.

Blue - Shortest route possible.

Yellow - Connect the two by going around the complete edge of the left face of the puzzle.

Green (from the lower left) - R5, D2, R2, U6.

Red - Complete the remaining path.

Solution #18:
Purple - Straight line.

Blue (from the right connector) - D2, L3, U2.

Green (from the left face) - D2, R9, U5, L/D3.

Orange (from the bottom connector) - U2, R1.

Yellow (from the left face, near center) - D2, L3, U6.

Red - Follow the path up and around.

Solution #19:
Yellow (from left face) - D1, L3, U6.

Orange (from left face) - U5, D/R1.

Purple (from right face) - U1, R2, D2, R2, U2.

Green (from right face) - L3, U2, L1.

Blue - Complete the remaining path.

Solution #20:
Red (from bottom) - R3, U9, L1.

Blue (from right face) - R1, U4.

Purple - Shortest possible route.

Orange (from bottom-most) - U3, R2.

Green (from left-most) - D4, R4, U2.

Yellow - Complete the remaining path.