Greetings!
I am currently working on breaking open Solatorobo myself. Those tools are very incomplete and don't seem to fully work.
If you use something like Console Tool or Tinke to look at the internal files of the game, you'll notice a couple of font-related files in the "contents" folder. These files contain standard NFTR font files that many DS games use, and you can use existing NFTR editors to work with them.
Most of the game's dialogue and text is found in the "script" folder. There is some sort of parsing framework around the text that is not currently understood, but you can modify the text with a hex editor and the game will handle it just fine. Line breaks are created by putting a 0x0A byte in with the text, the standard Line Break byte.
Your main problem is going to be reconstructing the CCB archives. Console Tool can extract them, but it can't put them back together once you make your modifications.
The good news is that I have written tools for this, and I will be releasing them on Github within the coming days.
Good luck!
