Hi John,

>There may be some. If the DLL is external to the project (and it may well have to be if you don't want to rebuild for each client) there will be a slight lag as the external process is called.

If I'm not mistaken, the delay happens only the first time the form is created, because the DLL is a new assembly that has to be located, validated and loaded. Any further access should be just as fast since it occurs in the same process and AppDomain.