CustomTableItem.New(string className, CustomTableItemProvider provider) from outside CMS

Hi,

I have a Core project, which contains a static class 'CustomTableHelper' that inserts/gets records from a Custom Table called 'Feedback'. The class responsible for the insert/get is the following:

using CMS.CMSHelper;
using CMS.SettingsProvider;
using CMS.SiteProvider;
using System;
using System.Data;

public static class CustomTableHelper
{
    public static DataSet GetData(TableType Table, string where, string orderBy)
    {
            string tableClassName = GetTableClassName(Table);

            DataClassInfo customTableClassInfo = DataClassInfoProvider.GetDataClass(tableClassName);

            if (customTableClassInfo == null)
                throw new Exception("Given custom table does not exist.");

            CustomTableItemProvider ctiProvider = new CustomTableItemProvider();

            DataSet dsItems = ctiProvider.GetItems(customTableClassInfo.ClassName, where, orderBy);

            return dsItems;
        }

    public static void CreateFeedbackHistoryItem(Feedback feedback)
    {
            CustomTableItemProvider customTableProvider = new CustomTableItemProvider(CMSContext.CurrentUser);

            string tableClassName = GetTableClassName(TableType.FeedbackHistory);

            DataClassInfo customTableClassInfo = DataClassInfoProvider.GetDataClass(tableClassName);

            if (customTableClassInfo == null)
                throw new Exception("Given custom table does not exist.");

            CustomTableItemProvider ctiProvider = new CustomTableItemProvider();

            CustomTableItem item = CustomTableItem.New(tableClassName, ctiProvider);
            item.SetValue("Name", feedback.Name);
            item.SetValue("Email", feedback.Email);
            item.SetValue("Phone", feedback.Contact);
            item.SetValue("Message", feedback.Message);
            item.Insert();
        }
}

I also have 2 sites, Kentico CMS Site (clean from any other code but Kentico), and my public Site (which consumes documents from CMS Kentico).

The insert/get works fine whenever I call the methods in Core from inside CMS Kentico Site.

However if I try to insert a new record on my Custom Table using 'CreateFeedbackHistoryItem' method from my public site (which also uses Core project), it throws and error on the item.Insert() line (it recognize the table though). (Note: If I run the 'GetData' method from my public site works fine and retrieves the rows).

It seems the problem is the Insert() method requiring some data internally.

Could you please provide a solution for inserting records in a Custom Table using the API from outside Kentico CMS?