Sub-Account implementation AX2012

Our ledger is pretty similar to the French one. I wonder how can I manage Sub-Account "Comptes auxiliaires"?

For example: An importation charges that are included incost price:

D:380.000 Achats stocké marchandises

C:401.102 | FM000035 Fournisseur marchandise

C:401.106 | FTRNS007 Transitaire (Came from Charges codes)

C:401.107 | FASUR005 Assurance (Came from Charges codes)

I tried to configure this using Financial dimensions but, I'm not getting the expected results as I coudnt attach "TRNS007" and "ASUR05" to their related accounts. I'm getting the vendor account populated next to 401.106 and 401.107 instead.

Could you give an idea how to implement them?

Thanks,