From Wojciech when I followed up about wanting the data from SAP BPC to Apptio:
If you would like to move it from SAP BPC, I would simply copy SAP table and save it as csv. From my experience Apptio is handling rounding to 15 decimal places.
Or, for automatic connection, if you have SAP BPC table present in some shape in SAP BW you can try data link connector into SAP (if you have on prem data link).
#Datalink