Rated 4 out of 5 stars

I'm a MAC user, and I loved this feature with Safari, and I'm glad it's now an add-on for my favorite browser.

Everything works alright, maybe in the future versions you can work a little on appearance. (Maybe something like the Beta Safari's version?) Not that the current look isn't good, varies from what theme you're using for Firefox.

One thing I really wanted to request though, if not possible already. For the Set Launch dial. I was wondering for when you set it to a file, maybe something like a Text file, if it could show you a preview for that file. Let you scroll through the whole thing like the thumbnails for web pages. I'd find that very useful. I think others might find that useful as well, if not just a handy feature.

This review is for a previous version of the add-on (0.9.0.3). 

I agree that the appearance could be better. The best would be to add Speed Dial themes/skins. It's in my to-do list for future releases.

As for your problem, after using the "Set Launch dial", I suggest that you enable the "Make thumbnail from" option from "Edit dial", use the "browse" button to locate that text file (or any file that can be rendered by Firefox without plugins), and set the "Scaling" in the "Layout" tab to "Fit horizontal". Unfortunately, Firefox can't make thumbnails of plugins.