using Umbraco 7.3.3 and Umbraco Forms 4.1.4

I got the issue that i cant seem to update record fields in a custom workflow when i set it to manually approve submitted records.

Dont update this way as i though it would.

public override WorkflowExecutionStatus Execute(Record record, RecordEventArgs e)
    {
        record.GetRecordField("Aktivitet").Values.Clear();
        record.GetRecordField("Aktivitet").Values.Add("MyCustomString");

        var fs = new FormStorage();
        var form = fs.GetForm(record.Form);
        var rs = new RecordStorage();
        rs.UpdateRecord(record, form);
        rs.UpdateRecordXml(record, form);

        fs.Dispose();
        rs.Dispose();

        return WorkflowExecutionStatus.Completed;
    }

Update the record, but crashes the server

public override WorkflowExecutionStatus Execute(Record record, RecordEventArgs e)
    {
        record.GetRecordField("Aktivitet").Values.Clear();
        record.GetRecordField("Aktivitet").Values.Add("MyCustomString");

        RecordService.Instance.Submit(record, e.Form);

        return WorkflowExecutionStatus.Completed;
    }

Updates the record field if not set to manuelly approve submitted records. If i want to manuelly approve the records, it wont save it to the fields, but it sends the field data that is not set with the currect value in a mail (if i select a workflow to send mail).

public override WorkflowExecutionStatus Execute(Record record, RecordEventArgs e)
    {

        record.GetRecordField("Aktivitet").Values[0] = "MyCustomString;
        return WorkflowExecutionStatus.Completed;
    }

I really need help here :)