I know you’re still waiting!
I have just fixed the shipping calculator for the store. It now knows how big each item is, and, hopefully, uses that information to calculate shipping correctly. Small UK orders (under 1 kg) are still £3. Small international orders (under 2 kg and shorter than 60 cm) are sent using Royal Mail Airmail, although you can choose a courier instead if you want. For everything else, I use whichever courier costs less. If that happens to be a lot less than what you paid, I’ll refund the difference. I expect the shipping calculator to make the occasional mistake the other way, too. If the error is substantial, I’ll have to email and ask for more money… I think it will get it right most of the time, though.
There is no longer any restriction on combining MakerSlide with anything else in the same order.
There is a problem with the 2 m lengths of MakerSlide, and only a small number may be available. Everything else will be in the shop in the next 24 hours or so, including the eShapeOko kits and the camera slider. I’ll post again as I add them.