Completely agree. And make copy/paste work as well, I tried to copy from v7 to v6, and Service Studio tells me I can't do that.

 Imho to compare it with word is somewhat simplified.

How should the downgrading commence?

As you all know upgrading is usually pretty straightforward.
but downgrading is really serious housework and effort.

if you upgrade you can keep track of the changes you have made
(conditional statement for example) so you can easily downgrade as well.

however, how can you tell if you start from 7.0 what would be the original starting point in let's say 4.2

i give you an simple example:
upgrade:
pattern A in 4.2 will be upgraded in 7.0 as pattern A
pattern B in 4.2 will be also upgraded to pattern A


downgrade from fresh 7.0 to 4.2
pattern A will be downgrade to pattern A or B.

Joost, nobody says it can't be complex. Also, nobody said anything about downgrading to 4.2. 7.0 is very similar to 6.0, and if it wasn't for strategical reasons it'd probably be called 6.1. But downgrading to the previous version (not any previous version) is in most cases very well possible, technically. That there may be exceptions doesn't mean it's a bad idea per se.

Some components are published in the network in version 7 or 6, but you are running a previous version

I read that as version 5.x or 4.X :)

on the copy/paste of 6.0 and 7.0 I would agree slightly more.

I am not saying it's a bad idea, but I wanted to add some different perspective to the idea.
Especially the implementation effort by OutSystems in contrast to the simple fact of opening up an espace in 7.0, watch what they have done and rewrite it yourself in your own espace (or ask the creator).
because, and these are my own assumptions,
a) the need for downgrading is rare and unique
b) chances are you are going to customize it anyhow for your specific needs.

I have to have version 4 and 5 still installed on my pc still because I might need to "upgrade" an espace from the network in order to find what I'm looking for. 

Moving forward, other options could be

• Allow versions 6 & 7 to open older Espaces
• Algorithm on the network to find these attachments and upgrade them to latest version.