@Buccaneer, thank you for submitting the feedback request. I found your post on the LaunchBox feedback website. I've upvoted the post, completed the "How important is this to you?" questionnaire, and added a comment. Here is @Buccaneer's feedback post for anyone wanting to upvote / provide comments:
Remember Expanded Sections in Platform Categories View
When I tried to changing the code it did keep the items expanded. However, LaunchBox would freeze on me and I had to use task manager to force quit the program. I would advise against changing the code. It could've been user error on my end, but just wanted to post my experience regardless.