Hello Bobby,
I would not say it's a sin, rather a priveledge to partake in the sedar. As long as you know what each thing means to the Jewish and how each points to and depicts Christ! I am not Jewish by decent. but to remember what we are saved from, depicted also in the plate, and the sanctification we have under Christ... There are certain things they do that I don't agree with, like having the children hide the bread... BUT..
I so look forward to taking of the communion at this time, the sedar! Remembering Christ and his ressurection!@ What a beautiful ceremony!