JBeaucaire says:
Create a macro called FixREF and paste this code into the window that pops up.
Code:

Cells.Replace What:="#REF", Replacement:="'Fcst template'", LookAt:=xlPart, _
SearchOrder:=xlByRows, MatchCase:=False, SearchFormat:=False, _
ReplaceFormat:=False

Now run the macro AFTER you put your new Fcst template file in place, it will repair all your broken formulas.
Tried that, placed the codes above into a new module, Sub/End Sub and then tried to run it but gives me an error Name argument not found and also it highlights "SearchFormat:=".

NBVC says:
Try:

Code:

=SUMIF(INDIRECT("'"&A1&"'!$A:$A"),$A6&"*",OFFSET(INDIRECT("'"&A1&"'!$A$1"),0,MATCH(C$4,INDIRECT("'"&A1&"'!$5:$5"),0)-1,65535,1))
Tried that too, there's still the #REF problem