A while since I last installed it, but don’t think you should have to give users Local Admin rights to run it. Needs to be installed with admin rights, for all users, and make sure all service run as fields are set to “Local System”. If you are installing on XP, I never have, there are a couple of things to look out for. Usual problem with legacy apps is permissions, as default XP does not allow access to anything in Program Files, you may need to allow all users full access to the AS400 Client directory. May also need to put users into Power Users group to run some legacy apps.