PS: im getting confused, you are giving me some good tips but i still have unanswered questions
Okay... I guess you need to tell me agian, what you want to know

how can i generate a .lib of a delphi dll ?
I don't really know what i lib is (i think it has to do with Linux), but i don't think you can do that.
Just using the DLL will be sufficient (unless you want your application to work on Linux or Mac).

i will use type def to define a own type of void type, and pass it on a argument to the exported plain functions of the class?
Sorry, i don't completely understand the question :? Maybe you can rephrase it?