I have used Smart Keyboard Pro on my DX for a WHILE with no issues whatsoever.
I put it on my RAZR and it wont predict text correctly.
For example if I type the word "somethong" it wont even correct it, it wont bring up the word "something" next to it in red.
There are other issues, for example, for whatever reason I saved the word "Missss" in my user dictionary and when i tried to type the word "is" which is a correct english word, it changed it to "Missss"
Here are the options I have enabled on the keyboard
T9 Next key
Show preview popup
Show alt Labels
In my "text prediction" settings, the following are checked:
Space after picking
Period on double space
T9 length priority
If there are options I need to have checked that I don't, or have ones checked that shouldn't, please let me know.