There is an error in the distance between gear centers, they are enclosed:

Apparently the error is in obtaining the basecircle radius, taking the value D instead of Db is solved:
change made:
reemplazar
block.append (CNC.grapid (Db / 2, 0.))
con
block.append (CNC.grapid (D / 2, 0.))

reemplazar
block.append (CNC.garc (CW, Db / 2, 0., i = -Db / 2))
con
block.append (CNC.garc (CW, D / 2, 0., i = -Db / 2))

Is this a correct solution?
D= diametral pitch, , should be correct.

Comparing with a gear created with another application, the lower circle should be smaller

The inner circle can be decreased by increasing the value of the clearence variable “c”
I have found it practical to include this variable in the values panel to enter