In a series-helpstalemate Popeye does not find a promotion dual in intelligent mode.
In the following example, twin a) shows a case where Popeye does not find a solution which starts with 1.g5 and has a queen promotion in move 11. Interestingly, Popeye works correctly after a minor change, see twin b).

Example Popeye input:
BeginProblem
Pieces
White Bh8 Kb5 Pd3 Qe3
Black Pg7 Pd5 Pe5 Ka1
Stipulation ser-h=12
Option Intelligent
Twin Move g7 g6
EndProblem

Popeye solution (v4.85)
a)
1.e5-e4 2.e4*d3 3.d3-d2 4.d2-d1=R 5.Rd1-d4 6.g7-g5 7.g5-g4 8.g4-g3 9.g3-g2 10.g2-g1=Q 11.Qg1-d1 12.Qd1-b3 + Qe3*b3 =
1.g7-g5 2.g5-g4 3.g4-g3 4.g3-g2 5.g2-g1=R 6.Rg1-g4 7.Rg4-d4 8.e5-e4 9.e4*d3 10.d3-d2 11.d2-d1=B 12.Bd1-b3 Qe3*b3 =

b) bPg7-->g6
1.g6-g5 2.g5-g4 3.g4-g3 4.g3-g2 5.g2-g1=R 6.Rg1-g4 7.Rg4-d4 8.e5-e4 9.e4*d3 10.d3-d2 11.d2-d1=Q 12.Qd1-b3 + Qe3*b3 =
1.g6-g5 2.g5-g4 3.g4-g3 4.g3-g2 5.g2-g1=R 6.Rg1-g4 7.Rg4-d4 8.e5-e4 9.e4*d3 10.d3-d2 11.d2-d1=B 12.Bd1-b3 Qe3*b3 =