Many of the jQuery based scripts on DD are written with jQuery in noConflict mode. This is intended to prevent more problems than it causes, and I suppose it may. But when another script on the page is using jQuery and not all of its code can work in noConflict mode, then that other script will stop working. There could be other problems. But there's a good chance that's all that it is.
To test this theory, reinstate the Nivo Slider and in the fluidtextresizer.js file, using a text only editor like NotePad, comment out the noConflict directive as shown:
Save that and use that version.
/*Fluid Text Resizer (June 27th, 2010)
* This notice must stay intact for usage
* Author: Dynamic Drive at http://www.dynamicdrive.com/
* Visit http://www.dynamicdrive.com/ for full source code
fluidtextresizer.count=(fluidtextresi . . .
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