La Grande Armée: The Campaigns of Napoleon in Central Europe and 1812: The Campaign of Napoleon in Russia are both by @ChuckS who is quite active, the latter with contribution by @Stiglr - who’s also relatively active. Did you use the forum to send a DM? Did you get a reply?
If nothing else, you could make the changes yourself and start a new project for each of these games. Consider to give enough information to stipulate which modules those will be based on and link to them, as well as give due credit to the authors.
Yours,
Christian