Error 429 creating object "pdfforge.pdf.PDFTools" in SignPDF script

I want to Sign a document using an action after saving, specifically, using the script SignPDF.

I am using the script SignPDF but it crash in the line Set pdfforge = CreateObject("pdfforge.pdf.PDFTools"). I recieve the err.number = 429 and exits.

I've tried other scripts and they work well (CopyPDFFile script), it seems that the problem lies in creating this kind of object because i can create others objects like "Scripting.FileSystemObject", "pdfforge.pdf.pdf", "pdfforge.pdf.PDFText" and others but i can´t create "pdfforge.pdf.PDFTools".

Can you help me?