fMath is almost impossible to use

Does anyone have experience using the fMath plugin?

We've recently udpdated from FCKEditor to CKEditor in Sakai (open source learning management system). We've included fMath as an option, and I'm trying to create a short user guide for it.

But so far, unfortunately...I'm finding it unintuitive, confusing, and so difficult for creating expressions that it's practically unusable.

The main difficulty is with how you select and manipulate items. There is an array of navigation and selection available with arrow, delete, return keys. But the cursor has very limited functionality, and once you begin creating math, navigation to a new cursor position seems next to impossible. One example: I added a superscript, and then tried to add a "minus" sign...but couldn't! I was stuck on the entry for the superscipt, and nothing I did would get me away from it.

Thanks in advance to anybody who's had luck with this plugin. We are still including the WIRIS plugin, which requires a fee after you generate a certain amount of images. But its interface, and ease of use, are miles above fmath.