Installing Datylon for Illustrator with Adobe Illustrator open can cause font problems.
If you see no or only a few standard fonts in your Typeface list in the Datylon for Illustrator plug-in, you might have installed the plug-in while Adobe Illustrator was still open.
These are the steps to fix it:
1. Uninstall the plug-in - How do I uninstall Datylon for Illustrator plug-in?
2. Clean the cache - How to clear the cache of Adobe Illustrator?
3. Uninstall Illustrator
4. Install Illustrator
5. Install the plug-in (with the Illustrator closed)
More about fonts here.