That errant window might be a holdover from something I fixed earlier... I'll have a look and see about fixing it.
Alright, that was a bug and I have it fixed, I'll upload a new version shortly.
As for limiting the stuff you can craft, currently, calling a specific craftType limits the recipes available by limiting the individual ingredients allowed to show up on the scene. To stop from crafting an alchemy potion on the blacksmithing category, you need to prevent alchemy items from being used in the blacksmithing category.
In the update I have just uploaded, I have made it so that a recipe will be immediately disqualified if it does not match the category of the current crafting category. This is probably how it should have been from the beginning, but I missed it by not having ingredients that were valid in multiple categories for testing.
Download the new version from your library, or the store page. Thanks for the report.