not distinguishing between the two
Instead of "Plants" and "Stationery", I've set the category to be numerical - 1 for plants, 2 for stationery.
I've added the first of those two custom conditions, one for the plant category (with a flat rate charge of £7.00):
WA_eCart_ConditionalTotal(PPcart, "TotalPrice", "Category", "1") < 10.01
...and one for the stationery category (with a flat rate charge of £5.50):
WA_eCart_ConditionalTotal(PPcart, "TotalPrice", "Category", "2") < 16.01
However, if I only have 1 product in my basket, let's say a plant, the cart is applying a £12.50 postage charge. In other words, it's charging both postage rates even though there's only one product in the basket and that product can only be from one category.
Also, we can have an empty cart, but the grand total is showing as £12.50 (the two postage charges). It seems that the postage charges are being applied regardless of whether anything is actually in the cart which makes me suspect that the custom condition is incorrect.
Hope you can help. Thanks.