Thats very weird because I tested out your project which has the same TWebPanel setter structure but yours work but mine won't...
Could it be my source file having something missing?
program ProXERP_Web;
uses
Vcl.Forms,
WEBLib.Forms,
Main in 'Main.pas' {Form1: TWebForm} {*.html},
Customer in 'Customer.pas' {Form2: TWebForm} {*.html},
Wrapper in 'Wrapper.pas' {Form3: TWebForm} {*.html},
Inventory in 'Inventory.pas' {Form4: TWebForm} {*.html},
Login in 'Login.pas' {Form5: TWebForm} {*.html},
MainInsert in 'MainInsert.pas' {Form6: TWebForm} {*.html},
Help in 'Help.pas' {DataModule1: TDataModule};
{$R *.res}
begin
Application.Initialize;
Application.MainFormOnTaskbar := True;
Application.CreateForm(TForm3, Form3);
Application.CreateForm(TForm4, Form4);
Application.CreateForm(TForm5, Form5);
Application.CreateForm(TForm6, Form6);
Application.CreateForm(TDataModule1, DataModule1);
Application.Run;
end.