How to get a refund - need advise

sir,
i am an NRI living in abroad since 2005..had worked for a short period in india wherein i took up a employment between jun 2010- may 2011 and left back for abroad after that.

i did had some TDS deduction while i was employed in india and i also submitted all  my home loan interest, principal proofs,principal and LIC policy investments.

i recently came to know through my 26as tax form, that there is a total TDS deduction of around 36k...

now below are my questions.

1, how can i go back and claim the refund for 2010-2011..
2. will i get the entire above amount as refund.
3. i understand there will be penalty if i owe anything..but what if i dont owe anything?,..
4. when i tried to do efiling..i could only go back until 2012.
5. also, is it true that NRI has a exemption limit of upto 2lacs and with that being the case, am  i eligible for a entire refund above ?
6. in case if i dont qualify as a NRI for that year ...can i file under a resident claim and get the refund.

please advise and appreciate your help in getting the  above refunded.