well it all depends how you migrate your objects?
- as an image?
- as a table?
and what objects you migrate?
- text object,
- listbox etc...
As you are brushing through right area you could have not consider, that NPrinting is running a dedicated account/user - so the setting in QlikView User properties needs to be done under this dedicated user on the machine where NPrinting engine/server is.
John is right in regard to appropach. Using excel functionalities (pull raw data, build excel charts instead and format them in excel is the best approach, cleaner and faster)
however if you are interested in Images you have to do steps i have highlighted - i have tested it and it works for Images