What do the 40, 17 and 12 counters mean?

They are routing checkpoints for the pink gate; use each return window to spend a short flower card before starting another long stack.

Why is Level 447 so long?

The video clears the sky, roof, house, flowers, lower path and perimeter in separate phases, so the last scattered petals are part of the solve.

Colony Flow! level guide

expert 9 colors

Lower the 40-to-17-to-12 pink gate with short flower colors, then pace the long dark-purple, white and green routes through the cottage garden.

If the player asks you to sign in, open the video on YouTube instead.

Tap pink 3, white 31, yellow 3 and pink 21, waiting for a return between long lanes.
Route dark-purple 53 and white 35 one at a time while the 40 gate begins to fall.
Use red-pink 18 and green 36 only after a white or pink hole returns.
Add green 38, white 40 and the next pink 18 as the gate passes through 17 and 12.
Clear the cyan sky and brown roof before taking another deep 35/40 stack.
Use yellow 2/4 and pink 2/5 to open the house and flower-center fragments.
Route the green 32/36/38 group and white 35/40 returns around the lower garden path.
Keep a lane for the blue-cyan and pink perimeter streams while blossoms separate.
Finish the brown roof, white border, green leaves, pink petals and red/orange path fragments.
Wait through the final border traffic and confirm the Colony Flow clear cue.

Colors in this level:

Pink, White, Yellow, Dark purple, Red, Green, Cyan, Brown, Orange

Opening dark-purple 53, white 35 and green 36/38 together hides the short key and flower cards at the gate checkpoints.
Stopping when the cottage is recognizable leaves the lower path, petals and perimeter border uncleared.

Open pink 3, white 31, yellow 3 and pink 21 before the deep dark route.
Stagger dark-purple 53, white 35 and green 36/38 through the 40/17/12 gate phases.
Save short yellow and pink cards for the flower-center and perimeter cleanup.

Board notes 5 details

Layout: A flower-covered cottage fills the board: brown roof, cyan sky tiles, pink blossoms, green leaves, white edges and a lower path. The pink-framed gate descends from 40 through 17 and 12. The opening stacks show pink 3, white 31, yellow 3, pink 21, dark-purple 53, white 35, red-pink 18, green 36 and green 38.
Goal: Lower the gate, peel the sky and roof, clear the house and flower field, then remove the lower path and scattered border petals.
Opening: Use pink 3, white 31, yellow 3 and pink 21 first. Add dark-purple 53 and white 35 only as return space opens, then pace green 36/38 around the short flower cards.
Danger Zone: Dark-purple 53 and white 35 occupy long lanes while the gate is still high. Taking green 36/38 and pink 18 together hides the short yellow and flower routes needed at the 17 and 12 checkpoints.
Mechanics: An extended multi-phase board uses the pink gate as a routing clock. The target moves from sky and roof to house, blossoms, lower path and small perimeter pixels before the final clear.

What do the 40, 17 and 12 counters mean?
They are routing checkpoints for the pink gate; use each return window to spend a short flower card before starting another long stack.
Why is Level 447 so long?
The video clears the sky, roof, house, flowers, lower path and perimeter in separate phases, so the last scattered petals are part of the solve.