When you set the vB Version at newthread.php, it defaults back to 3.6.5 when submitted and you have to edit the modification to make it a different version.
When you initially create a new hack, the 'options' like supported and version don't take. It's been that way (for me anyway) for as long as I've been posting hacks here. You always have to edit after you post.
I don't know what you two are referring to here - when you create a new thread (in the mods area), options like supported are not available. All you can set is the prefix and vb version, and both of those are saved as set.