[Plugin: WordPress Uploads] tested and didn't work

Q 1)
I added a bunch of extensions allowed, as such:

pdf
doc
docx
xls
xlsx
csv
txt
text
xml
jpeg
jpe
gif
png
bmp
zip

And added one as denied:
jpg

And I tried uploading a .jpg file and it let it go through.

Did I not enter these properly (then instructions need to be better) or did the plugin not work?

Q 2)
If I don’t add extensions in the Allowed column, will they be Denied by default? Or are all typical WordPress upload file extensions permitted still unless explicitly Denied?
(reference: http://codex.wordpress.org/Uploading_Files#About_Uploading_Files_with_WordPress )

Thank you.

http://wordpress.org/extend/plugins/uploads/