Following discussions with DreymaR elsewhere, here's an idea of what a French version of Colemak could be like. (Sorry for the HORRIBLE image, I'm definitely not a GIMP expert. I'll make a nicer one for the final version! - at least you can easily see what's changed with this one...).
(1) It's not based on AZERTY. AZERTY is horrible (why would you need to use Shift to type a dot?) and I think it would be rather hard to use without Caps Lock (AZERTY actually requires using Shift for numerals).
(2) My idea was to preserve as much of standard Colemak as possible and not to make it too hard for US keyboard owners by making the extra key too important (this is pretty selfish, I bought my MacBook in the US).
(3) Ç is still at AltGr-C. Ù is done via AltGr-R + u, but I guess another option could be to make the ` on the extra ISO key a dead key in which case it could be used for that. As ù is only used in one word and a not hyper frequent one at that, I think that's fair enough.
(4) The ability to type Icelandic is lost which I hope is not too much of a problem.
(5) I'm not sure about the relative placement of è and à - any usage statistics anyone? My guess is that è is more frequent but I'm not sure at all, and also that the circonflexed/tréma-ed characters together (using the dead key) are more frequent than è and à.
(6) Too much strain on the right pinky? Any solutions to that at all?
I would be grateful for comments... and for DremayR to deliver on his promise to implement the final version (when we thrash it out) for Windows ;)