>I try to debug a custome Ole Automation Server build with VFP, but is not possible (?). How do it?
>

What do you mean? Do you need to run the server inside the VFP debugger, or can't access the features of the server? You're not going to be able to run an in-process server directly under the debugger, since the VFP in-process server can't have an UI elements in it, and it'll be instanced in the same process address space as the process that starts it. You may be able to run an out-of-process server either as a separate VFP session instanced before the client is started, or a remote out-of-process server instanced on another system before you try to access it.

>And, how build a graphical interface for the server? (a Exe..), i.e. show a form in the server and display the number of user, etc...

The .EXE can have any UI you'd like it to, but you can't directly expose that UI in the context of the client application, because the server is not running as a part of that application.