System Crashes and Issues with Online Profile

Here is my system I am running.
      Windows 7 Ulitmate 64 Bit RC 7100
      Nvidia GeForce 9700 GTS 512mb
      RAM:  4gb
      CPU:   Intel Duo Core 2  2.00GHZ

When the game is running like it should it runs perfectly with good frame rate and only needing to bring textures down to High.  However here are the problems I am having that is impacting the game and sometimes making it unplayable at times.

1)  Random system crash were I am forced to hard reboot it.  Doesn't seem to have a set time as there are days I will go a couple hours with no crashes and days like today were I can't go beyond 10 minutes.  I have turned off UAC and even set it to run as an admin just for giggles but the crashes still continue.

2) Sometimes when I am enter the main menu my online profile states that I am logged in but when I resume the game I get a warning saying that the downloaded content I have installed is not authorized.  I would have to close the program down and restart it to get it to work.  I am wondering if the bouncing in and out of the online account is impacting the crashes. 

3) Also is there a way to play the game offline with your download content as I travel for work and at times I will find myself without an internet connection.  I can see why they won't to implement this to keep from ripping it off but this also impacts those that may not have constant internet connection.

I had similar problems with Mass Effect but once I turned off UAC I no longer crash on that game and it runs awesome with full details and audio.  Performace wise my computer runs fine as many of the new games out like Modern Warefare 2 run great in high detail and frame rate so any help or if like many others await for a patch to fix it. 

This is a great game but sadly with the number of crashes I am having is impacting the gameplay as it is more frustrating then fun which means no desire to keep playing.  Hopefully can get some answers from Bioware techs. 

Here is an update on more info on my problems.



1) 90% of the crashes are always during dialogue and when it happens the screen goes black and that last audio noise is repeated over and over and does not stop like a studder. I am not able to open task manager, close the program and only a hard reboot clears it.