Hello
using Joomla 1.5.20 with your Plugin I can't get pdf button working correctly. I tested that deactivating the plugin and clicking on core PDF creation icon in all articles, it works fine. Activating your plugin it open a blank window.
I tested with default template too.
I don't know why, but this is.

Does it work with a default template if the plugin is enabled?

No, as said I tested with default template too

It just wasn't clear on that last point.

I just tested on a couple of my sites and .pdf button is working fine, with JB Libray enabled.

Do you have a link you can share?

Yes:
www.vorrei.org/lavori/50-lavori/2746-il-crollo-del-mito-casa.html
To be complete, there are 3 plugins that give this issue on this site. Disabling those, pdf works fine. Of course I tested activating every one separately and pdf doesn't work.
They are JB Library 1.0.10, mfBlank 1.1 and RSForm Pro 1.2.0

or developer version:
vorrei.selfip.org/vorrei/lavori/50-lavori/2746-il-crollo-del-mito-casa.html
with default template, JBLibrary 1.1.3 active and Alpha Toolbar disabled.

Thanks a lot for your attention.

Sorry, I cannot trouble shoot this for you.

It is clearly not an issue with the plugin, as I have tested it on several other sites. Also you can see on our demo site that pdf creation works fine.

Your template is clearly not the standard Joomla default installed templates, and you have a lot of additional components.

I recommend you first switch to JA Purity or Beez and then try it. If it still doesn't work, look at your components.

A blank page is usually a sign of a php error, so switch errort reporting on and you may get a clue.

thank you

No problem.