Mary,
If this is your first pair of Dansko's it may take a little time to get use to the support. Dansko has some of the best support in the industry and some peoples body need to adjust for support. I would not recommend putting more support in the shoes as it will change support and fit. I would recommend having a shoe store stretch the leather a little on the side you are having the discomfort and see if that will put your foot into a better postion. Some peoples feet need to adjust to the fantastic support that come in the Dansko. This shoe has them most support in the industry and some people body need to adjust to this. I know because I went through it my first time.
Also the cabrio leather is great but it can take time to loosen up as it is a little stiffer at first. I hope this helps out.

The best fit in a Dansko Professional is to have room. This model is supposed to fit loose all around the foot almost to the point that it feels big. This is a good indication that you have the right size. You want your heal to slip up and down in the back. You do not want your toes touching. Best way to tell is put on a sock that you would normally have on and put on the shoes. You should have around a pinky's width of room in the back of the clog.

Short answer is that if it feels tight I would probably get a bigger size. Wear them in your house and see how this feels. The fit on the clog is totally different then any company out. You will get use to the loose feel and they usually become your favorite shoes. Enjoy and I hope they work out for you.

The difference is the Leather the leather used on the upper. The oiled and Pull up leather is softer out of the box and cabrio is a little firmer leather. The sole is the same through the professionals. You get the same benefit from all of them. Oiled leather is the most durable leather and easy to maintain. Cabrio is very dressy and easy to clean. Pull up is a soft leather but is a littl harder to maintain, but very good looking.

The cooper has a removable insole that can come out, you should be able to put your orthotics in it. This shoe has great arch support to begin with and some customers can wear it without an orthotic. It carries the Seal Of Acceptance from the American Podiatric Medical Association, which means doctor approved shoes. With the support in this shoe it will help with your Plantar Fasciitis. Being a 4e you probably would want to buy one size bigger to accommodate your extra width. This shoe is not built as a wide shoe.
Good luck.