I recently installed ore dictionary and factorization to my already stacked minecraft and I have had similar problems to the one I am facing now with other mods such as ic2. nei I have found is very buggy (no offence chickenbones) and will crash when I try to load a world. The fix for ic2 was to delete the recipes which was ok for me because I have played ic2 so much I know most of the recipes but this is the first time I have ever played factorization. I have 64 bit, Quad core processor, windows 7 if that helps at all. I installed all mods through forge. Here is ingame error log, if you need more info just pm me.
Minecraft has crashed!
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Minecraft has stopped running because it encountered a problem; Ticking screen
A full error report has been saved to C:\Users\Owner\AppData\Roaming\.minecraft\crash-reports\crash-2012-12-08_09.57.49-client.txt - Please include a copy of that file (Not this screen!) if you report this crash to anyone; without it, they will not be able to help fix the crash
Minecraft has crashed!
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Minecraft has stopped running because it encountered a problem; Ticking screen
A full error report has been saved to C:\Users\Owner\AppData\Roaming\.minecraft\crash-reports\crash-2012-12-08_09.57.49-client.txt - Please include a copy of that file (Not this screen!) if you report this crash to anyone; without it, they will not be able to help fix the crash
Thank you for taking your time at looking at this!
P.S. As a side note how do you put a spoiler tab (kind of a noob in the forums).