Panel Builder - Version 3.51 Prevent costly errors when laying out and pricing glass block windows. Panel Builder will draw glass block panels for window openings or walls based on the dimensions you supply. The program displays the number of each size block required and will calculate the costs of materials with sales tax, using pricing information that you tailor for each account. Build solid or vented panels. Position the vent where you want it. Add up to 5 different size vents to custom panels. Add dryer blocks and change panel layouts. Set password protection for block and vent prices as well as accounts.