Ammani said:
Who told you that?!? You are free to choose the visa Office I guess.
No, you are not free to choose visa office.
Please see the link below to understand which VO is responsible for PR visas based on your country of nationality or country of residence.
http://www.cic.gc.ca/english/information/offices/apply-where.asp
Abu Dhabi Visa Office doesn't process PR visas.
If you are resident in Kuwait for more than a year, your visa office should be London.. But also you can choose visa office based on your country of nationality.
Kuwait = Federal economic immigration applications are processed in London