I had no problem at all using the official
EQ2MAP Auto Updater with the streaming updater (I don't normally use it, but I installed it just to make sure the EQ2MAP updater works ok). You set the Everquest2.exe to the one in the Streaming updater folder, and you use the options button to set the "Autolaunch EQ2" executable to Launcher.exe.
Not sure why your other UI install is not working properly. All you should have to do is extract the eq2.ini to your /EverQuest II Streaming/ folder and then the DrumsUI folder to /EverQuest II Streaming/UI/. Do that first, then run the EQ2 Auto Updater and it should update EQ2MAP over your DrumsUI installation.