Please add Guppy Trading Sytem based on GMMA with stops and Counter Back Line. Or replace the script language so it was possible to make (as it was sugested it could be made as add-on for C++ for example).

What are you using in this screenshot? Is that a spetial add-on to MetaStock?

OB:=Input("over bought level",-20,20,0);
OS:=Input("over sold level",-20,20,0);
Sys:= Input("Systems[1]Signal [2]OB/OS levels",1,2,1);
Display:= Input("Systems[1]Signals [2]Indicator",1,2,1);
M330:=If(OscP(3,30,E,%)>0,+6,-6);
M535:=If(OscP(5,35,E,%)>0,+5,-5);
M840:=If(OscP(8,40,E,%)>0,+4,-4);
M1045:=If(OscP(10,45,E,%)>0,+3,-3);
M1250:=If(OscP(12,50,E,%)>0,+2,-2);
M1560:=If(OscP(15,60,E,%)>0,+1,-1);
A:=(M330 + M535 + M840 + M1045 + M1250 + M1560);
B:=Ref(A,-1);

{* Entry conditions *}
entry:= {<- Do not change entry parameter name}
If(Sys=1,Cross(A,B),Cross(A,OS));

{* Exit conditions *}
exit:= {<- Do not change exit parameter name}
If(Sys=1,Cross(B,A),Cross(OB,A));

{Display}
If(Display=1,entry,B);
If(Display=1,-exit,A);