Not working pluguin attachment for virtuemart 2

Good Morning.
We just bought the pluguin attachment pluguin for virtuemart, I have installed, activated pluguin and created the custom field, but when I try to upload a file in tab custom field product, let me select the file but it is not saved and do not shows on the web.
We are using joomla 2.5.20 and virtuemart 2.6.6, can I have indicate which is the error and how to fix it?

Hi,
Thanks for contacting us. I apologize for the inconvenience. Before uploading the file, you first need to save the product after adding the attachment custom field because javascript doesn't work in virtuemart before saving any custom field. Are you doing the same?

Good afternoon.
Right, I add the field and save, then choose a file and displayed as selected, but when you save the file does not appear as if there had been loaded.

Hi,

When you add the custom field, there is an option to set yes or no for "is a Cart Attribute", You need to choose "no" here. And there is another option to enter the layout position, Default virtuemart positions are ontop, onbot, normal, You need to check what your tab plugin supports and enter accordingly. If it doesn't work. Please send us your back end and FTP login details via Contact Us form. We'll look into it...

Good Morning.
About your answer, this is not the problem. The problem is that you save the document, I sent the login details to the email support@wdmtech.com, thank you very much.

I await your comments.