Dll separation question

[Martin Wilck]

I am sorry to say that I still don't quite understand this issue, but -
can anybody point me to a resource saying what exactly I may or may not
do when writing code for a wine DLL? In particular, when writing code
for DLL X, which functions from other DLLs may I call?

Example: When writing netapi32 code, can I call advai32 Registry
functions to obtain config options, or do I need to use the (IMO rather
awkward) ntdll interface ?

Btw: Dll separation is a really complex issues and I think I'm not the
only one who feels he doesn't quite understand what it means. IMO winehq
needs a very clear description of that somewhere where it's easy to
find.

Martin