It is possible to link posted credit documents to a CFC futures contract where the status is Activated . and/or Finished. You The user should not be able to see contracts that do not have this status, where forward rate is 0 and Posted document amount is 0.
Link CFC
Open the posted credit memo that needs to be linked to a futures contract. Under Actions and Currency Future Contracts choose click on Link CFC.
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The system filters on all posted invoices with the same Bill-to customer and Currency as on the credit memo. Be careful when selecting the correct futures contract in question. If there is any uncertainty, check the futures contract beforehand. Select the futures contract to link to the credit memo.
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Click on OK.
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When we take a look at Now the Credit Memo has been linked to the futures contract , we can see that we have got another line in “Posted documents” fast tab: and can be found under the Posted Documents tab
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Un Under the “General” fast General tab, the “Posted Linked Documents Amounts” Amounts will be applied:
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When linking 
To link a second Credit memo to a CFC we have a check after selecting a CFC that if there is a posted invoice that matches the credit memo we are linking.Memo go through the same steps as shown above. The system notifies the user after selecting the futures contract.
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If No is selected here you get an error , “Link Cancelled” error will appear and the process is stopped.
If Yes is selected, you get a check the system notifies the user if there is are more or the same number of credit documents and invoices linked to the CFC. If there are more invoices than credit memos we allow the system allows the link to go through else there is an error and the process is stopped.
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