My goal is to split the node edit page with the main field forms staying on the default one (the add page itself or mynodeurl/edit), and some additional field forms on the other pages (e.g. mynodeurl/option & mynodeurl/otheroption).
I think the best way to do this (and the way I want it to work) would be using a couple of variants for the node add/edit page (Panels Module), with the url path's being filtered through the string: url path selection rules.
I have no idea how to make the string url path selection rule work like that (I practically dont know anything how the string url path's selection rules work for the node (or node add\edit pages) at all, since I've only seen people implementing the url path based selection rules on custom pages and never on nodes).
How I've tried to solve it
I've done some playing around setting url path's like: /option option /option nodetype//option etc. to the node template and the node add\edit form variants, the only thing that worked is when i set my main node view variant to trigger when: Current path is not "/option" , and set the additional variant to trigger when Current path is "/option", the exactly same thing didnt work for the node add\edit page. (see http://shot.faintrush.me/xfvu1c0aic.png <- this screenshot).
The only working variant is using the Node template page, and adding forms there doesn't work which makes it useless for me. (If you know how to make forms work on the Node template page you'r also very welcome to answer here).
Of course the */option is probably not the best thing to put there, it's just the only one I found that's at least a bit alive.
By default my url's work as I have explained here -> https://drupal.org/node/1993068 (i made those url aliases being created automatically but in a different way from using a pathauto + a custom token) To make the links like siteurl.com/nodetype/25/edit work i use the sub-pathauto module (i have tried setting the sub-pathauto url depth to 2 and accessing siteurl.com/nodetype/25/edit/option with the settings on the screenshot above - didn't work).
More additional info
I also tried to make this work by creating a custom Page with the /node/%node/option path and assigning %node the Node edit form: node ID context, but then I'm running into another problem because the Node id doesn't actually match the url path and there's no way for me to assign the right context to the node edit form - the unique content type node id that i'm using in urls (again, read the issue from the link a bit higher) is not to get by any token or variable, the url alias is just being generated once by the rules module.
I posted the same issue (written in a little bit different words) to the drupal official website issue queue to the panels module but there seems to be no activity there for a couple of days so I'll give it a try here.
Any help would be appreciated!