The suggested warning has been added finalization step.

If a "__import__" builtin lives up to that point, and no "--recurse-directory" 
option is given, then a warning is issued. This should avoid situations where
this went undetected. Nuitka now indicates that it may need help there.

Fix will be in 0.3.19pre already

Enhanced import mechanism to work with module name, level, and from_list to work 
as expressions, which may be optimized to constants during the run time, which 
are then statically imported.

Should still consider a warning for unresolved imports, that --recurse-directory 
may be necessary for them.

The use of "__import__" was ignoring keyword parameters given. This would lead to 
packages e.g. not importing submodules.