You can compile a listing of Skylines from info in this thread
http://www.bladeforums.com/forums/showthread.php/1253124-Kershaw-Skyline-list-of-models and this thread
http://www.bladeforums.com/forums/showthread.php/1152494-%28in%29Complete-list-of-Kershaw-knives. If you have questions about any particular models, I might be able to help you.
In terms of the HoB Halloween blade, I'm not certain. I saw one for sale on the auction site and asked the seller if I could see more pictures of the blade but never heard anything back. I don't know if it ever actually auctioned off because initially it wasn't making reserve. You might try to contact HoB to see what they can tell you about it? I've dealt with them before and they've always given good service.
I'm a little leery of listing imprinted blades as unique models and worthy of collecting. Heck, I could buy a vanilla Skyline, send it out to have a custom design lasered on the blade and call it a sprint...but it really isn't. It's just a custom. The key is whether the model was made and designed by Kershaw, not third party. I tried to get a "Shot Show 2015" Skyline on the auction site a while ago but didn't get it. I refused to go crazy with my bid because I couldn't verify if it was a run made by Kershaw for Shot or something that Shot did as a giveaway. It was nothing more than a vanilla Skyline with an imprint on the blade. Some examples of imprints that I consider legit would be the "40th Anniversary", "Snap On" or "First Production" imprint knives as they were produced and imprinted by KAI.
I have an inventory of all of my knives in Excel and I'm fairly sure that I have a complete collection of all of the unique models of Skyline with the exception of the "Ducks" version. There are a few one-offs made by Kershaw as gifts...I know Sticktodrum and Nutnfancy have special gift versions...but with the exception of those, I have a complete collection and can post a list here later.
My concern is that there hasn't been a special model Skyline since the HoB orange/black and the BladeHQ CF/S30V models...meaning there hasn't been a Skyline release in 2015. I'm worried I might be missing one. If anyone has any knowledge about new Skylines, please share.