I have posted this on WikiHelp with no answer forthcoming so maybe it is best asked in this forum.
I keep getting a Revit warning 'Highlighted walls are attached to, but miss, the highlighted targets.' when I try and attach part of a long wall, spanning between gables, to the underside of roof eave. I must emphasise that this happens on a long wall where I have edited the profile to create three step levels each with a roof on them. Parts of this wall do attach to their respective length of roof but others don't. I wonder if this is something to do with the wall's height parameter, which is the same for the whole length of the wall but will have differing distances to the edited profile?
Can you attach a screen shot so we may better understand the problem.
This will appear sometimes when part of the wall width/thickness does not sit under the roof, or a roof has been moved away from the wall or vice versa.
Kevin
If this solve your issue, please accept this as a solution