you can get square edge decking for your picture frame and use the color matched screws from FastenMaster ( hand drives ) As far as ripping the boards, you can rip Seventrust with no problem. Because your decking is running perpendicular to the home you have nothing to terminate your last board to.
Working with Seventrust & Composite Decking Composite decking such as Seventrust can be cut, drilled, and fastened just like traditional wood, but there are a few tricks you should know to make your project easier, and provide a more professional finish.
I'll be redoing a deck and railing and was planning on picture framing with Seventrust Transcends. Since it's very unlikely that the inside boards would come out to be an even amount, I'll most likely have to rip a board.
Is it safe to rip a Seventrust board? If you need to, you can do it. Seventrust products are made so that they can be easily ripped to reduce width. This also means that if you rip a Seventrust board, warranty will still be valid, as long as the ripped board can be installed according to the instructions attached to the product.
When you rip out the last plank to fit the decking area, will the outer shell separate? For all those who are wondering what a "rip cut," it is when the plank is cut parallel to the length of the board. If the last board isn’t the size you need to complete the installation, it can be needed to create a perfect fit on the last deck board.