I am among those very few who were given immigration to Canada , but due to family/personal reasons decided not to pursue it. Now it is more than 5 years and the PR Card has expired and we are disqualified all together.

Also, with changed circumstance and mind set , I plan to reapply , and have some questions related to it , hope people could advise me :

1. Where in the application process , should I mention (which I want to) that I was a previous immigrant who had a PR card etc but was now reapplying due to personal reasons. Maybe that information (addendum) may help in qualification.

2.In previous case we were not asked for proof of english language skills , but now the rules are different and evidence is required although not necessary if one can prove it. I have been enducated throughout in an english medium school, University education was a BE (in english medium, ofcourse) and worked in India .. and abroad in UAE and Saudi im IT Consulting...
Can some one please advise what proofs / evidence should be presented just to prove that my bacground was in english. or do we have to give an IELTS ?

3.I am having a residence visa of Dubai and my family is living there . Six months back I got a job to work in an IT project in Saudi where also I am holding another residence visa (of saudi). Every fortnightly i am visiting my family in Dubai. In the form IMM008_Ie (schedule 1 / background declaration) section 6 - my current country of residence should be what ... ? UAE or Saudi ? if it is Saudi .. would the application go to Riyad (Saudi) , since I would prefer to be processed at UAE (Abu Dhabi)...as I don't plan to continue for long to work in Saudi..

4.Similarly for Police clearance for which one have lived for six consecutive months or longer.. do i also need to get a certificate from Saudi ..although I am travelling everymonth out of the country to UAE but holding a residency / work permit of Saudi?

5.If i want to later apply police clearance for Saudi but living outside Saudi would the embassy e.g.Saudi embassy in UAE arrange the documents ? any one had experience please share..

I can answer points 2 & 4.
IELTS is now mandatory and you do need to have police clearance cert. from Saudi.
Rest of the points can be well answered by experts on the subject like pratickm.

First of all you have to check that your proffession comes in the list of 38 categories.
Then there are questions in the application asking you about have you ever applied for the visa. So at that point give the answer truthfully and explain the sitauation on a separate sheet.

So better put Saudia and explain on a sheet of paper that you have residency of both but as your family is in UAE you prefer to have your interview in UAE.

except IELTS all other issues are complicated. IELTS is mandatory. filling IMM form would a tedious job for u buddy.