I think I may have cracked it myself...I had another post and somebody helpfully advised me about '(blank)' not being blank at all..another story entirely. But, my formula is:
=IF(AV5="(blank)",IF(AX5="Y",CONCATENATE("Funding under our organisations ",AK5," funding programme for a ",AT5," project titled ","'",D5,"'",". This project is a ",AI5," project, with a focus on beneficiaries from a BAME background."),IF(AY5="Y",CONCATENATE("Funding under our organisations ",AK5," funding programme for a ",AT5," project titled ","'",D5,"'",". This project is a ",AI5," project, with a focus on beneficiaries with a disability."),IF(AZ5="Y",CONCATENATE("Funding under our organisations ",AK5," funding programme for a ",AT5," project titled ","'",D5,"'",". This project is a ","AH4","project, with a focus on younger beneficiaries."),IF(BA5="Y",CONCATENATE("Funding under our organisations ",AK5," funding programme for a ",AT5," project titled ","'",D5,"'",". This project is a ",AI5," project, with a focus on older beneficiaries."),IF(AND(AX5="",AY5="",AZ5="",BA5=""),"",CONCATENATE("Funding under our organisations ",AK5," funding programme for a ",AT5," project titled ","'",D5,,"'",". This project lists its main activity as ",AI5,".")))))),CONCATENATE(IF(AX5="Y",CONCATENATE("Funding under our organisations ",AK5," funding programme for a ",AT5," project titled ","'",D5,"'",". This project is a ",AI5," project, with a focus on beneficiaries from a BAME background."),IF(AY5="Y",CONCATENATE("Funding under our organisations ",AK5," funding programme for a ",AT5," project titled ","'",D5,"'",". This project is a ",AI5," project, with a focus on beneficiaries with a disability."),IF(AZ5="Y",CONCATENATE("Funding under our organisations ",AK5," funding programme for a ",AT5," project titled ","'",D5,"'",". This project is a ","AH4","project, with a focus on younger beneficiaries."),IF(BA5="Y",CONCATENATE("Funding under our organisations ",AK5," funding programme for a ",AT5," project titled ","'",D5,"'",". This project is a ",AI5," project, with a focus on older beneficiaries."),IF(AND(AX5="",AY5="",AZ5="",BA5=""),"",CONCATENATE("Funding under our organisations ",AK5," funding programme for a ",AT5," project titled ","'",D5,,"'",". This project lists its main activity as ",AI5,"."))))))," This funding has contributed towards a ",AV5," - ",AW5))