accessibility and usability: where is the attach node button?

Sorry for this question but for me is very important.
I'm visual impaired and I use drupal without problem. Today I installed webfm because I must re-organize all my files, due to migration in drupal6 and my old filemanager, disknode, doesn't provide a stable version in d6.
So, I installed the module, but, unfortunately, I'm not able to attach a file into a node.
I'm using user1, so I have all privileges, and I assigned webfm permission to page type of content.
In fact, when I modify a node, I match the "webfm attachments" section, I activate it and I activate the file browser.
Then I scroll down to a file, I make a click with right mouse button and appears a menù, well, this is not very confortable using a screen reader but in this menù I find:
rename, delete, copy to cliboard, paste to edit (or similar)... but I can't find attach to node.
Where is it this item? is it the first of the menù or the last?
I hope someone can help me, unfortunately when I click with left button into a file, for example a mp3, it doesn't attach to the node... it opens windows media player!
It should beautiful if this particular behaviour would be controlled by a settings, for example, what do you want click of left button do?
"view the file, attach to node, download... etc".
Thanks.