hi MrTheme.

First, I'm sorry my too late answer.
And it looks quite good to create converter from cbb to d3forum.

But I've never tried CBB at all...
All I know about CBB is that made by phppp and is an old style module with dirname "newbb".

Then, I have to learn how to install it into my environment, for creating the converter.
(I've already removed xoops.org version XOOPS 2.0.x from my environment)

Can CBB run with ImpressCMS?

If it's true, I'll install both ImpressCMS and CBB, and test them.