There are 8 per box.
Wall installation is not advised because it is not covered under warranty.
Unfortunately, we do not have the density rating of our cork products. I can give you the weight/ft² of the cork you are referencing (HL9310LS is the model number) for comparison. That would be 1.99lb/ft².
Cork flooring is great in bathrooms settings, due to its soft feel and natural anti-moisture properties. The height issues may be resulting from the tile being a certain height and things installed in the bathroom according to that height. If that is the case, you would have to install a flooring of a matching height. Our 7mm laminates may be a good choice for you.
To get a sample for this product, please visit this link and have it shipped to your home or to your nearest Home Depot, http://www.homedepot.com/p/Home-Legend-Lisbon-Spice-Cork-Flooring-5-in-x-7-in-Take-Home-Sample-HL-659563/203190512
10 feet times 5 feet = 50 sq. ft. One would need 3 cases of this product to cover 50 sq. ft.
I'm not sure what you mean by "square edge." This product does not come in a tongue and groove such as what would be nailed down. This product is click and locking for a floating installation. When "floating" the flooring a foam underlayment is recommended; when gluing it down you won't be able to use an underlayment because the flooring will need to be glued directly to the subfloor. For more information on installing cork flooring follow the following link:http://www.homelegend.com/pdf/installation/cork-installation.pdf
This product has a click and lock system and is "floated" no glue necessary.. It can be installed below grade providing a moisture barrier is laid first
The effectiveness of doing so in unknown. Designed as flooring this product has not been tested for wall application and no warranty is applicable when not used for its intended purpose.