For those who care here is a small VBS program to test the QuickPDF ActiveX capabilities.

Boris, this test was made specially for your problem. It shows that the PDF creation it works as expected. But of course I have never used the 5.11. Please register the latest ActiveX dll (5.21) and try again:

<Test cmd-file="test.bat">
cscript //nologo PDFTester.vbs
rem will generate file: testdrawtext.pdf
rem with 1 single page.

copy testdrawtext.pdf testdrawtext-2pages.pdf
cscript //nologo PDFTester.vbs testdrawtext-2pages.pdf
rem will modify testdrawtext-2pages.pdf
rem and add a second page.

open testdrawtext.pdf
rem must have 1 page with your text at 100,500

open testdrawtext-2pages.pdf
rem must have 2 pages, both with your text at 100,500

rem for a custom test run
cscript //nologo PDFTester.vbs test1.pdf
rem as result you should see your text appended to test1.pdf
rem document
</Test>

<Script filename="PDFTester.vbs">
option explicit
on error resume next
' The main proc
call main(WScript.Arguments)

' On error Quit with exit code 1
if Err.Number <> 0 then
 WScript.Echo "Error # " & CStr(Err.Number) & " " & Err.Description
 WScript.Quit(1)
end if

function main(args)
    dim iPDF
    set iPDF = CreateObject("iSED.QuickPDF2")

    if iPDF.UnlockKey("your quickpdf key") <> 1 then
        Err.Raise vbObjectError, , "Cannot unlock PDF library"
    end if

    if args.Count = 0 then
        call processPage(iPDF, 1, "testdrawtext.pdf")
    else
        dim i
        for i = 0 to args.Count - 1
            WScript.Echo "Process: " & args(i)
            if iPDF.LoadFromFile(args(i)) <> 1 then
                Err.Raise vbObjectError, , "Cannot load pdf document: " & args(i)
            end if

            dim ndoc, npage
            ndoc  = iPDF.SelectedDocument
            npage = iPDF.NewPage

            call processPage(iPDF, npage, args(i))
            call iPDF.RemoveDocument(ndoc)
        next
    end if

    set iPDF = Nothing
end function

function processPage(iPDF, npage, pdffile)

    call iPDF.AddStandardFont(4)
    call iPDF.SetTextSize(10)
    call iPDF.SelectPage(nPage)
    call iPDF.DrawText(100, 500, "SOME TESTED TEXT")

    call iPDF.SaveToFile(pdffile)

end function

</Script>