Apart from A500 + ACA500 reported IDE issue, I tested EmuTOS a bit more and there are following issues I faced:
1) A1200 + Blizzard 1230-IV + 64 MB FAST: no Fastram detected on welcome screen (this line is totally ommited, shows just ST-RAM). That was tested on 2 Commodore Amigas 1200 + 2 different Blizzards 1230 (another A1230 is my friend's who tested, too)
2) FDD LED keeps lightened even after floppy is not being read anymore (and keeps spinning, too), it stops only after (at least) warm reboot.
3) my friend has newer-type Commodore Amiga mouse (more round one) , which works 100% correctly under AmigaOS. Yet with EmuTOS it behaves weird, after few clicks of left button (in random situations), EmuTOS gets frozen like left button is still pushed. You can still move the pointer, but it acts like button is pushed as if it happens over a GEM window, it moves the window without button being actually pressed. There's no other help than reboot for it (till the next button "freeze"). It doesn't happen under AmigaOS (believe me), it's just EmuTOS mouse routine looks confused by this otherwise working mouse
The rest is looking really good and promising, I've had a lot of fun playing with it! If you need some more tests to conduct in the future, I'll be happy to help.
And yes, keeping fingers crossed for ACA500 IDE-CF working with EmuTOS one day
Thanks again for all the great effor you've put into EmuTOS.