Best Practices for Fillable forms with Firefox

I'm new to the product, so please forgive a possibly ignorant question. I have created a PDF with Text Fields in PDF Converter Professional 8.1. These populate and render fine in IE, Chrome and mobile Safari. However, Firefox has a known bug with displaying fillable PDFs. Ultimately, I'd like the text fields to be non-editable anyway, I just want to present users a good looking, pre-filled form.   

I have been searching the forum, but I can't see anyone else reporting this. Am I missing something like Form.Lock or maybe a way to detect Firefox's selected plugin for viewing these?

I am using the following code in ASP.Net(VB) with version 9.16:
            'Count the number of form fields in the loaded document
            Dim FieldCountAcroForms As Integer = QP.FormFieldCount()
            '// Loop through each form field on the selected page
            For i As Integer = FieldCountAcroForms To 1 Step -1
               '// Determine form field type
               Dim eFldType As DLL.FieldType = QP.GetFormFieldType(i)
               Try
                    Select Case eFldType
                        Case DLL.FieldType.Text
                            If Not System.Web.HttpContext.Current.Session(QP.GetFormFieldTitle(i).ToLower) & "" = "" Then
                                QP.SetFormFieldValue(i, System.Web.HttpContext.Current.Session(QP.GetFormFieldTitle(i).ToLower) & "")
                            End If
                            If bFlatten Then QP.SetFormFieldReadOnly(i, 1) 'Lock it
                        Case DLL.FieldType.CheckBox
                            If CType(System.Web.HttpContext.Current.Session(QP.GetFormFieldTitle(i).ToLower), Boolean) Then QP.SetFormFieldValue(i, "Yes")
                            If bFlatten Then QP.SetFormFieldReadOnly(i, 1) 'Lock it
                        Case DLL.FieldType.Signature
                            Dim sDbg As String = "Sig field " & QP.GetFormFieldTitle(i) 'Don't lock
                        Case Else
                            Dim sDebug As String = QP.GetFormFieldTitle(i) & " Type" & eFldType.ToString
                    End Select
               Catch exArg As ArgumentException 'Column not in table
                    'Try to catch exception for duplicated column name
               Catch ex As Exception
                    Dim sDebug As String = ex.Message
               End Try
            Next

The loop goes backward because I made an attempt to Flatten the fields using Flatten and UpdateAndFlatten. I would appreciate any help. Thanks in advance.