S!
Yes, IL2 works with ATI. But for now before the driver update you have to use some "workarounds" to get rid of the "blue hue" and "blocky text" which are the most striking errors when using ATI.
Blue hue workaround is very easy to solve, just open conf.ini and set UseVertexArrays=0 or in IL-2 setup disable Use Vertex arrays and you are done. No more blue hue.
Blocky text has 2 workarounds. First one is to use either Catalyst 9.10 drivers OR drop the atioglxx.dll from the 9.10 package to IL-2 root. Then you have no blocky text. Second workaround is to launch game, play a track and wait for the blocky text to clear. After that it does not appear again.
So the most annoying bug is this blocky text as you can not join games in Multiplayer via HL or similar as the game loads graphics BEFORE the GUI and it is the graphics that cause the blocky text. So basically if not using the dll file in IL2 folder you have to start game, play a track and then join server via IP from IL2 Multiplayer.
Third and least desireable option to clear blocky text without using workaround files etc. is to set HardwareShaders=0 thus disabling Perfect mode in OpenGL and use Excellent instead. Or use DirectX mode that looks..pale and no-one uses it anyway
So ATI does work with IL-2 with some problems with it. Performance is good though. So the driver update will hopefully solve these annoying bugs.