Ok, here are some proposals for improving the UI:
– grey out unavailable icons
– highlight better if scrolling is available
– optionally add a page indicator if it is still not clear enough
– mark new craftable things as “new”. (not sure if this is really needed. Haven’t unlocked a new thing yet or never noticed ^^)
– group similar category tabs together, so it’s more clear that they are crafting similar stuff (i.e. weapons, barricade improvements, tools,…)
Edit: Hmpf… can’t add images and dropbox doesn’t like to share a preview, so I added a direct link. Sorry for that. Not sure if you would like if I add pics to imgur or similar pages.