Form 1045 is for Carrybacks not Carryforwards.
Further, just for your information, the dates for filing Form 1045, even for NOL carrybacks for those years has passed.
From the 1045 instructions:
When To File
You must file Form 1045 within 1 year after the end of the year in which an NOL, unused credit, net section 1256 contracts loss, or claim of right adjustment arose.
Normally, you would have to file for a Carryforward using Form 1040X.
If your 2012 return is under examination, you may be able to get the NOL recognized by the agent rather than having to Amend your 2012 return after the IRS has made their proposed adjustments. You would want to inform the agent or the examiner of the availability of your NOL from 2010.
Do you know if you elected to carryforward the NOL on your 2010 return?
If not, you must go back 2 years before going forward and since the 2008 and 2009 returns are closed, to the extent that the 2010 NOL would have been absorbed by 2008 and 2009 before going forward to 2011 (which is also closed), I'm afraid that your 2010 NOL will be substantially depleted by the time it gets to 2012.
Basically, if you didn't elect to carryforward the NOL, you'll lose the NOL that would have been absorbed by 2008 and 2009, as well as 2011 as all those years are now closed.
If there is any NOL left after that, it would be available for 2012.
Depending upon what is in your tax returns for those years, and how readily available they are, it could be somewhat of a project to sort that all out.