Hello Francisco,

Welcome to ConTeXt! You are sure to enjoy it here.

> My conclusion is that *lettrine* does not work correctly with Mark-iv and
> there is somewhere a bug that has to be corrected. But I could be
> mistaken. Am I doing something wrongly?

No, you are correct, there is a bug. It happens on my end, too; I have
attached the resulting output.

\usemodule[lettrine]
\starttext
\lettrine[Lines=3]{T}{he two} typeset arguments are the
dropped capital. \input knuth
\stoptext

I had a look at the module code, but it's too low-level for me, so I'm
CC-ing Taco Hoekwater who wrote the module. Depending on how trivial
the bug is, and how busy Taco is, he might be able to help.

Kind regards,
Sietse
Sietse Brouwer