I purchased the product that says it can be used for 3 windows, and could barely cover one. Regardless, that's a whole different issue...I was dismayed when, as I attempted first to seal the top edge across the top edge of the window. The adhesive was not particularly sticky on the leftmost side (as I began to unroll the film), and continued to pull away on the left side. Then as I read the instructions further, the instructions stated that the product was not recommended for use on plaster, painted surfaces, or stained wood. I'm curious, are there any surfaces this product IS recommended for? My walls are sheetrock covered in light texture and then (of course) painted. I suppose per the products disclaimer that would explain why it continues to pull away from my walls as I try to shrink it...If I'd read closer, I'd have known that, but again: what CAN this product be used on???