help! NOCs and job experience questions

I've done a lot of research, but after it all, I'm still a little unclear on things.

I gradated from a Canadian University about two years ago, and I worked here for 10 months as a "sales assistant." Before I got the postgraduation work permit, I tried to get an LMO for this job; I did it recklessly and it was rejected, since they thought it was like a retail sales job.

Now I'm trying to apply for the CEC, and I don't want to make the same mistake again. I suppose my job is more like a secretarial job (which is #1241: Secretaries in the NOC... that's considered skilled, right?). Should I have my previous employer state that I was a secretary, not a sales assistant? Or should I just assume that my duties will state it for me, and on the form, put down that it's similar to 1241?

One final question about proof of a NOC code. My current job is a step down from my last job, at least skill-wise. I'm appealing with my employer to write a job experience letter stating that it has more responsibilities than just a "salesperson" job (which it does), in hopes it might be considered skilled. Will this work?

Thanks so much for reading this. I really, really appreciate it.