Hi Bull Island Man,
Thank you for your review. However, we do not show you purchased the product from us. Please check your receipt again. We're sorry your situation didn't work out. We do have great installation instructions on our site located in the "Specifications Tab". Also, it does say, "For joints with depth greater than 1/2" (12 mm), the caulking depth must be controlled by a closed-cell
backer rod." Thus the 3/4" was just too thick, and was the main cause of your issues.
Thank you,
The Koffler Team