Hi,
It's probably something in your browser. Try Firefox or Chrome and see if you get success.
Here, I use Firefox and never had any problem with nabble's apps.
Yes - am sure it's on my end - same wif inserting images -
I can’t seem to put a jpg/gif in my own posts -
But i have had several members put from a small gifs/jpgs to a big 2 page screen shots - and they came in great...