After many happy years of running a mkii set up I am finally facing the fact that time has moved on and upgrading to mkiv. 

I understand the biggest change needed to my sources is in the fonts handling, but I am getting a few other problems with things like chapter/sectioning setups that I can't see mentioned in https://www.contextgarden.net/MkIV_Differences 

I was wondering if there exists a comprehensive "what you have to change in your sources to move from mkii to mkiv" document anywhere or, failing that, if anyone can offer guidance on what has changed in the chapter/sectioning setups code between the two.

Apologies for not supplying an example of code - I'm not yet at the point that that's possible.

Any help much appreciated. And hello to anyone who remembers me from fifteen plus years ago!

Duncan