Is there anyone using Clientdatasets with mssql7 without problems??

The situation;

I'm using TQuery. Create the sql at runtime. Connect Tquery to
TClientdataset. (TQuery->TProvider->TClientDataset->tDatasource). We're only
edit one table at the same time. The SQL statement looks like "Select * from
City".

The City table looks like:
CityID    Identity
Name    varchar(50)

1) When we try to insert a new record we get suche a message about
"inserting null fields in the identity field". When we try to change a
setting we get the message: "record changed by another user"
What going wrong?

2) When we use a TQuery with a static query ("Select * from City") and add
persistens fields everything worked! But when we change the updatemode of
the provider to upWhereKeyOnly the update doesn't work anymore. I want only
to update the fields through de ID field and not with all the fields. Is
this possible?

Any reply more than welcome!!

Thanks,

Richardo