Is there any summary of new MUI code format?

I upgraded from NSIS 2b3 to 2b4. I understand that the MUI has a new format incompatible with its older versions. I looked at its documentation, but there is no section for upgrading previous MUI installations - does this exist or does one have to look at the new syntax to try and fix an existing script? Thanks!

The MUI documentation works as a step-by-step for new installers, but being that there have been so many MUI versions an upgrade section isn't really possible (although a b3 to b4 one would be a good idea)
You will just have to compare syntaxes (and yes this can be tricky with large scripts!)

-Stu