How can we insert a data record into an SAC planning model

We have a requirement where we are giving a simple user input screen to user in SAC. We have to save the entered data to a planning model with few dimensions. Can you please share some information on how we can insert data records into a planning model? Can this be done using Data actions? The measures in the model are actually irrelevant. We only need to save dimension information to be used for a few custom admin functions within SAC. We are able to update dimension members using create members planning function but this is not what we are looking for(this doesn't create any data rows in the model). We are also able to update the key figure values in a the model using the setuserinput function along submit/publish(This helped with only updating the key figure values but this doesn't post a new data row in the model). But we are unable to insert a completely new transaction record into the SAC planning model.

We are planning to use Analytic designer to make this happen. Can anyone suggest on what the best way is to fulfil this requirement?