First, make sure you've got current Java installed. Java 7 is best. Then go to
http://updater.pala.de/ and look for the Launch button in the first section. That'll launch and install the updater itself and create the desktop icon that'll let you launch it without going to the web site. It'll ask you for where your EQ2 game folder is, and then install the ProfitUI files into it.
Note: DO NOT try to save the file the Launch button gives you. Open it the Java Web Start. If you save it to your computer and try to use it, it won't work right. You need to run it directly so it'll install the updater's software into Java's application cache correctly.