*Bivouac / chamonix challence from infogrames also had a TO8 version with almost exact same graphics as Amstrad's.
It is to notice that As as TO8 featured a 4096 colours palette and the same resolutions/, the French developpers already had the experience when dealing with Amstrad Plus games.
As a result, if upgrading those games for the Amstrad Plus, just getting the exact same graphics as the TO8's counterpart would be enough.