Hello Sebastian!
I'm sorry to hear about this issue; I'm happy to help! Thanks for the screenshot you shared; it's a big help for me to understand the problem.
The picture of the hand with the cotton swab is a partially rotated rectangular image, and only the tip of the swab needs to be counted as a hotspot intersection for the action to register in Storyline.
That being said, from your list, items A to C are not currently possible. We cannot set Storyline to ignore the neutral space nor remove the object's background. To indicate a specific part of the object to count for intersecting, your suggestion in item D should work.
Unfortunately, I tried item D and grouped a smaller shape with the image but ran into the same issue with the blank preview; this is a bug that we are currently monitoring:
Apologies for any trouble this has caused. We're still looking for a fix, but we'll notify you once it is available. Here's a peek into our process:
As a workaround, I suggest using a long rectangular picture that shows only the cotton swab to eliminate the extra spaces that may interfere with the interaction.
I attached a sample Storyline project file based on your description to illustrate a possible way that the workaround can be executed. Please let me know if you have any questions regarding the sample project!
