When you trying to convert into macro big amount of already connected nodes, after convertation those nodes inside of a macro will have randomized order of connection to the output and input of a macro. It is quite uncomfortable - i think macro should save primary order of connections from input and to output
you can notice randomization even by just looking on colors of wires
The difficult thing here is, we, as humans, can easily think “yeah connect from top to bottom”, but that is sadly not easy for a computer. I therefore do not think this is easy to fix
Something I’ve been doing instead (and this trick is also great for copy pasting), is putting checkpoints at either end! These will often prevent randomisation and, if it does happen for some reason, you only need to rewire the checkpoint, and not all the individual nodes connected to that checkpoint.