#VALUE error trying to insert a named range to SUMIF with initials

Hi guys,
I'm trying to create a rota spreadsheet where staff are working in different areas and paid different rates, so I'm trying to use a formula to select all cells with each staff's initials in (e.g. "A.B.") within a named range that covers several separated columns.
It doesn't matter which formula I try I get an error value. I can use the following array formula for one or two columns but it falls apart when I try to use it over the range : {=SUM((LEN(B4:C66)-LEN(SUBSTITUTE(B4:C66,"K.A.","")))/LEN("K.A."))} works, {=SUM((LEN(HOMESUPPORT)-LEN(SUBSTITUTE(HOMESUPPORT,"K.A.","")))/LEN("K.A."))} doesn't. I have tried basic =SUMIF(HOMESUPPORT,"K.A.") which hasn't worked either and various other ones, I just want it to add up all cells with certain initials in within the named range and I'm really stuck, please help!

='Staff week 1'!$B$4:$C$66,'Staff week 1'!$F$4:$G$66,'Staff week 1'!$K$4:$L$66,'Staff week 1'!$P$4:$Q$66,'Staff week 1'!$T$4:$U$66,'Staff week 1'!$Y$4:$Z$66,'Staff week 1'!$AC$4:$AD$66

ah bugger, oh well slow way it is, thanks for your help anyway!