Problem in creating BDC code

Dear experts,

We have DEV client 150,250. Dev occurs on 150.It has very less data and not configured.

Client 250 has enough data and configured at par with PRD.

Now i want to generate a BDC code for F-02 posting.

In 150 i cannot complete the cycle becuase it is not configured.In 250 i cannot again because

it has no authorization for writing code it says 'SAP system has status not modifiable.'

But i can complete BDC cycle of recording only in 250.

Waiting for your recommendations.