That sounds just like the problem i had!
Assuming it is the same problem, cutesoft have added some new properties to the editor which changes the default behaviour! It caught me out and now it seems to have caught out cutesoft themselves as shown in the demo link!
http://cutesoft.net/example/Edithtml.aspx
Which is why if you add new properties you should default them to whatever the previous version did.... (sorry just a little ranting there!) I found it very annoying especially as we did not know what new features had been added.
Anyway the new property you need to set to false is.......
EnableStripStyleTagsCodeInjection
Look out for
EnableStripLinkTagsCodeInjection
EnableStripIframeTags
Hope this helps!