Note the error "unterminated procedure". The input region (starting with far left ">") ends before the procedure. Being lazy, I just exported the worksheet as 1D maple input then edited it. It runs. Note that FirmModelPP does not reference parameter alpha.

restart;
with(plots):
c := 1:
cr := 0.0300000000*c:
u := 1:
sExp := 0.0600000000*c:
s := 0.6500000000*c:
v := 3*c:
FirmModelPP := proc(alpha, delta)
local p0, xi0, q0, Firmpf0, G0, Recpf0, Unsold0, Environ0;
option remember;
xi0 := 1; p0 := min(s + sqrt((v - s)*(c - s)), delta*v + sExp);
q0 := u*(v - p0)/(v - s);
f(N) := 1/u;
F(N) := N/u;
G0 := int(F(N), N = 0 .. q0);
Firmpf0 := (p0 - c)*q0 - (p0 - s)*G0;
Recpf0 := (sExp - cr)*xi0*q0;
Environ0 := G0 + q0;
Unsold0 := G0;
return p0, q0, Firmpf0, Recpf0, Unsold0, Environ0;
end proc:
FirmModelFC := proc(alpha, beta, delta)
local p00, xi00, q00, Firmpf00, G00, Recpf00, Unsold00, Environ00, pr00;
option remember;
xi00 := 1;
p00 := s + sqrt((v - s)*(c - s));
if p00 < delta*v + sExp then q00 := u*(v - p00)/(v - s);
f(N) := 1/u;
F(N) := N/u;
G00 := int(F(N), N = 0 .. q00);
Firmpf00 := (p00 - c)*q00 - (p00 - s)*G00;
Recpf00 := `ξ00*q00*`(sExp - cr);
Unsold00 := G00;
Environ00 := q00 + Unsold00;
else q00 := alpha*u*(v - p00)/(v - s);
f(N) := 1/u;
F(N) := N/u;
G00 := int(F(N), N = 0 .. q00/alpha);
pr00 := p00 - delta*v;
Firmpf00 := (p00 - c)*q00 - alpha*(p00 - s)*G00;
Recpf00 := (beta*(pr00 - sExp) + sExp - cr)*xi00*q00 - 1/2*(pr00 - sExp)*beta^2*xi00^2*q00^2/(u*(1 - alpha));
Unsold00 := G00;
Environ00 := q00 + Unsold00;
end if;
return p00, q00, Firmpf00, Recpf00, Unsold00, Environ00;
end proc:
CurrentMetrics:= proc(alpha,beta,delta) option remember;
local p, q, Firmpf,Recpf,Unsold,Environ;
if (FirmModelFC(alpha,beta,delta)[3]>=FirmModelPP(alpha,delta)[3]) then
p := FirmModelFC(alpha,beta,delta)[1];
q := FirmModelFC(alpha,beta,delta)[2];
Firmpf := FirmModelFC(alpha,beta,delta)[3];
Recpf:=FirmModelFC(alpha,beta,delta)[4];
Unsold:=FirmModelFC(alpha,beta,delta)[5];
Environ:=FirmModelFC(alpha,beta,delta)[6];
else
p:=FirmModelPP(alpha,delta)[1];
q:=FirmModelPP(alpha,delta)[2];
Firmpf:=FirmModelPP(alpha,delta)[3];
Recpf:=FirmModelPP(alpha,delta)[4];
Unsold:=FirmModelPP(alpha,delta)[5];
Environ:=FirmModelPP(alpha,delta)[6];
end if ;
return p,q,Firmpf,Recpf, Unsold,Environ;
end proc:
plot(['CurrentMetrics(alpha, 0.2000000000, 0.2000000000)[3]']
, 'alpha' = 0.0000000000 .. 1.0000000000
, 'linestyle' = ['solid']
, 'legend' = ["Firm's profit with delta=0.2"]
, 'labels' = [alpha, "Firm profit"]
, 'labeldirections' = ["horizontal", "vertical"]
, 'color' = ['blue']
, 'axes' = 'boxed'
);