I have three of the animal series grills and Crisco seasoning is the best as far as I am concerned, BBQ Paint introduces it's own issues down the road after use.
As far as a cover goes, either the factory outlet stores or also check out the covers available at your Home Depot, should be about 4$ -9$ for that size, that's where I got covers for my cooking tables, be careful with the packaging and if the size is not right, exchange it.