Version .50 and higher we have updated the ?appwin to open in the same tab/win. We also added a new option ?newwin to allow you to have it open in a new window.
URL to use for new window:
http://{qieServer}:{port}/qie/launcher.html?newwin
Default of a using the same window/tab:
http://{qieServer}:{port}/qie/launcher.html?appwin
Note: you must specify laucher.html with the ?newwin option for it to work.