Question: Is there any official way how to update client itself (=> how to distribute changed 'iuclient.iucz' file)?
Sorry about that, it'll be fixed in the next version.
2) When the option "Execute file after updating has finished" is activated, the BUILD UPDATE will fail with an error message:"Update build error...: Object reference not set to an instance of an object" which is not very clear to me. Question: What's wrong?
Well, in this upcoming version I've changed how updates are built, so this bug might not even exist anymore. But, I don't want to take that risk. Could you explain how the process to reproduce the bug? That is, which folder are you adding it to (i.e. Application Base Directory or Temp Folder), and what additional options are you using (command line switches, waiting for executing to finish, etc.)?
Also, does it fail with every *.exe you try to execute?
-Wyatt