Hey, I am having trouble getting 菸 to be interpreted by the program like I'd like it to be, when I enter it, it gets changed to

烟 yān: cigarette; tobacco; smoke
菸 yān: cigarette; tobacco; smoke

if I enter it singly, or just 煙商 [烟-] yānshāng: tobacco merchants if I enter as part of the word 菸商.

I am in Taiwan, so perhaps usage is different than elsewhere, but my book (Practical Audio-Visual Chinese 5, 2nd Edition) differentiates and I'd like to memorize it along the lines my book and teacher have provided.

You can create a custom definition of any word to meet your needs. On the iOS version you just tap the pencil icon beside the current definition and save it as a personal definition, but I'm not sure how to edit the definition on other platforms.

I've updated the character mapping for the word 烟商 to be consistent with your textbook and you should now see the word 菸商 when you're studying.

The reason you're seeing both 烟/ 菸 when entering a single character into a vocabulary list is because our system is displays both the simplified and traditional characters and letting users choose the appropriate character variations based on the context, in this case either 烟/ 菸 or 烟/煙.

Hopefully the update should allow you to study the correct characters from the textbook!