Dear Owais - There could be many reasons for the rejection of the documents. If you have constructed your application package in accordance to the guidelines provided within the check list, there should not be any issue with it. They calculate points elgibility based on the factual data provided, if something is missing they are not gonna make any guess. The most common errors are:
a. people forget to sign any of the application forms.
b. if applying as a family, information about spouse is missing or signatures.
c. mode of payment - by credit card - if your card declines the payment. DD is secured.
d. Canadian educaton equaliavance - attach the orignal letter along with copy of the transcripts.
e. experience letters are very important as they provide a base to attain the required marks. so these should be close to the mentioned requiremnts
f. proof of birth - birth certificate should be provided. Passports are not accepted for this purpose.
and list goes on.......
i hope and wish the missing experience letter will not have any impact as your self claimed points are 67. so be positive and hopefull.
Your NOC-2134 is building up very strongly from mid november, the last update showed 204 and it seems CIC is processing mid - end Dec 2013 applications. Based on that i am quite optimistic you are definately in. Good Luck
Regards