When I tried to make a blueprint in creative, when I clicked some land marks and then tried to remove them, the red lines stayed there. Also with the architect, some weird things were happening.

This happens because objects are not properly unlinked in https://github.com/BuildCraft/BuildCraft/blob/6.5.x/common/buildcraft/builders/TileMarker.java#L265-L270. Just making a note here to check it out with more detail later.

Yeah, land markers work completely differently now so this sort of thing will happen in different ways.

this has been fixed with the rendering rewrite of 1.8+, can be closed

What. Reproducible?

Haven't tried recently but I remember this happening and I also think I posted of a way to reproduce it.

ask chilm about this, remember seeing this heapen once on his stream

One bug with land marks is that if you place 2 land marks (let's say "A" and "B") and connect them by right clicking "A", then you place another lank mark "C" adjacent to "B" (not to the one you right clicked before) and then right click "C", "A" won't connect to "C".

The other one is harder to reproduce. Here's a way: http://youtu.be/1oZoXSxLSbo

@psxlover - the video is private

Oops sorry about that, it should be ok now.