PowerPivots Plus Time Capsules Expert
Here is an expert that goes long when crossing the Prev months high, goes short when crossing the previous months low. 
You will need the PowerPivots Plus Add-on 

Highlights 

Long 

TCH:=ExtFml("PowerPivots.TimeCapsules",H,3,1); 
TCL:=ExtFml("PowerPivots.TimeCapsules",L,3,1); 
LE:=C>TCH; 
LX:=Cross(TCH,C); 
SE:=C<TCL; 
SX:=Cross(C,TCL); 
B:=ExtFml("PowerPivots.SysEval",LE,LX,SE,SX,"!@#$#@!"); 
B>0 

Short 

TCH:=ExtFml("PowerPivots.TimeCapsules",H,3,1); 
TCL:=ExtFml("PowerPivots.TimeCapsules",L,3,1); 
LE:=C>TCH; 
LX:=Cross(TCH,C); 
SE:=C<TCL; 
SX:=Cross(C,TCL); 
B:=ExtFml("PowerPivots.SysEval",LE,LX,SE,SX,"!@#$#@!"); 
B<0 

Out 

TCH:=ExtFml("PowerPivots.TimeCapsules",H,3,1); 
TCL:=ExtFml("PowerPivots.TimeCapsules",L,3,1); 
LE:=C>TCH; 
LX:=Cross(TCH,C); 
SE:=C<TCL; 
SX:=Cross(C,TCL); 
B:=ExtFml("PowerPivots.SysEval",LE,LX,SE,SX,"!@#$#@!"); 
B=0 

Symbols 

Long Entry 

TCH:=ExtFml("PowerPivots.TimeCapsules",H,3,1); 
TCL:=ExtFml("PowerPivots.TimeCapsules",L,3,1); 
LE:=C>TCH; 
LX:=Cross(TCH,C); 
SE:=C<TCL; 
SX:=Cross(C,TCL); 
B:=ExtFml("PowerPivots.SysEval",LE,LX,SE,SX,"!@#$#@!"); 
B>0 AND Ref(B,-1)<=0 

Short entry 

TCH:=ExtFml("PowerPivots.TimeCapsules",H,3,1); 
TCL:=ExtFml("PowerPivots.TimeCapsules",L,3,1); 
LE:=C>TCH; 
LX:=Cross(TCH,C); 
SE:=C<TCL; 
SX:=Cross(C,TCL); 
B:=ExtFml("PowerPivots.SysEval",LE,LX,SE,SX,"!@#$#@!"); 
B<0 AND Ref(B,-1)>=0 

Long Exit 

TCH:=ExtFml("PowerPivots.TimeCapsules",H,3,1); 
TCL:=ExtFml("PowerPivots.TimeCapsules",L,3,1); 
LE:=C>TCH; 
LX:=Cross(TCH,C); 
SE:=C<TCL; 
SX:=Cross(C,TCL); 
B:=ExtFml("PowerPivots.SysEval",LE,LX,SE,SX,"!@#$#@!"); 
B=0 AND Ref(B,-1)>0 

Short Exit 

TCH:=ExtFml("PowerPivots.TimeCapsules",H,3,1); 
TCL:=ExtFml("PowerPivots.TimeCapsules",L,3,1); 
LE:=C>TCH; 
LX:=Cross(TCH,C); 
SE:=C<TCL; 
SX:=Cross(C,TCL); 
B:=ExtFml("PowerPivots.SysEval",LE,LX,SE,SX,"!@#$#@!"); 
B=0 AND Ref(B,-1)<0