I have the following objects in my NameMapping repository: Aliases.App.MainForm.MdiClient.GridForm.AutoHideContainer.SelectionPanel.SelectionPanelContainer.grbSelection.GridForm_SelectionGrid Alias...
When using Aliases, it's best to try and shorten the name e.g. Aliases.GRBSelection.SelectionGrid as it's easier to script and maintain.
It's also best to refer to, if possible, rows and columns or cells, as opposed to creating name mappings for each row. For example, Aliases.GRBSelection.SelectionGrid.Cell(19, 1).
When doing var janusSelector = "Aliases.GRBSelection.SelectionGrid" + rowIndex + ".Janus_Selector"; you're assigning a string to a variable. Since it's not an object, intellisense will not understand it - it's basic intellisense!
You can use the eval() function to evaluate the string and return its complete value. For example, var janusSelector = eval("Aliases.GRBSelection.SelectionGrid" + rowIndex + ".Janus_Selector"); will return the actual object.