Looks like you have identified a problem with the FX retrieval from Sage 50.
You will need to upload BOTH the Simply database where you feel that the retrieval is not working as well as a backup of the FX database.
I will also need the sysadmin password for the Sage 50 data. Please email me this information as well as any other info you feel will be useful in helping to resolve the issue.
Be forewarned that if this turns out to be a FX problem a solution may well take months!