First thing I see is that you are using patch v1.3.3 along with NPC mod 3.4. On the one had this version of the mod is designed for patch v1.3.4 only. But on the other hand neither patches nor mods currently alter Cleo's behavior. My be problem is caused by something else.
I need to reproduce the case on my side. Can I have your saved game done BEFORE th bug appearance to Alchemist [aT] Fromru [doT] Com? Also I need to know exact version number and release date present in the header of the readme.txt found in the root directory of the installation CD. Or what is more preferable you can just check your disk with validator from
that topic. And the last thing I need to know: have you completed Necklace quest before trying to ask Cleo about Loxley?