The finditem returns will be local to each 'tab,' but euo can only process one thing at a time since it depends on the client to return the information. finditem is a really slow and somewhat intensive function in euo, and will likely interfere with your other scripts. I'm about at the same place where you're at with multiple scripts running together, and can tell you it's time to learn about globals...
http://wiki.easyuo.com/index.php/Documentation#NamespaceThe only thing that I run independantly is my bandage script, as other than targeting, it does not interfere with any other client function.
I'm no expert when it comes to globals, yet, but I can tell you you probably need to send global pauses to pass the processing to whichever script needs to run finditem
*there are a handful of helpful threads here at scriptuo dealing with global namespace