There's a few small mistakes with the ISO-UK keys:
- 1! should be 3£
- \¦₩| should be \|₩ (| instead of ¦ and no fourth sublegend)
- `¬ should be `¬¦
- If you want, you can also include 4$€ for complete coverage including sublegends.
Also, the F13 should probably be black instead of white.
Now, would you consider including basic (Korean) ISO support in the base kit? This consists of the following keys: ISO Enter, 1.25u Shift, R3 \|₩, R4 <>. You could then have the UK-specific keys in the add-on kit, as you currently do. This would make ISO support less expensive, and would make the add-on kit cheaper, too. If I'm not mistaken, some Korean keyboards are ISO, so to me it makes sense to have basic Korean ISO support in the base kit.
On a different note, your base kit is missing a second 1u Alt key to go with the 1.5u Super and 1.5u Function for Mac bottom rows. So you could either add the missing second 1u Alt, or remove those two 1.5u keys.
Finally, feel free to remove the 1.75u key from the space kit, as that size is used
only on 40% boards (and only three of them, at that).
