We currently are replenishing our stock and it will get back on sale. Totem Mini Lab is one of our oldest product and it is still being supported and developing. We will continue to sell it and don’t have plans to discontinue it.
I am planning to use an old laptop running “Windows 7”
Using Windows 7 should be fine as long as Arduino IDE supports this operating system version.
From hardware side TotemDuino uses USB-to-Serial chip to communicate with a computer.