Funny you should mention this... Crosslink.
I believe I can help you with a lot of what you are looking for. Scrollbar UI - I can help, no problem. Moving files, click and Drag, I think I can help you. I need to glean a better understanding of what you are looking to do. However, from what I read, it looks like you and I operate in similar ways. Others can hopefully chime in, too.
Yes, each issue should have its own separate thread. This helps keep everything neat and organized and helps users find solutions to specific problems.
Could you please knock this O.P. to One issue, then make the rest into a thread for each one?
Finally... You said you write books.
I believe you. 