>One more related issue. Why < g > (note the space after less sign) is not allowed? It's not a tag.

In regards to this, after having looked at it, I will keep it as is. Basically, the acronyms should be entered as listed in the http://www.levelextreme.com/Help.aspx page in the Acronym expansion section.

As for the tag issue, whatever is between the less than or greater than sign is considred a tag in HTML and will be interpreted. The UT parser works the other way. We define what we allow. The rest falls in the rejection list. This is like that since last year because there are too many HTML tags to deal with and new ones can occur at any time. So, we define what we allow for maximum security and parsing issues.