if AmiKit 9 works fine on your Mac while Flower Pot does not, please check if you have correct ROM files (including the rom.key) you're copying to Flower Pot's ROMs folder.
The thing is that both packages use the same version of WinUAE and Wine, so the only difference is in OS emulation (68k vs PPC).
Anyway, please try to use newer or older version of Wine. Flower Pot includes Wine2.0.
There's a slightly newer version (2.1) available.
Download both archives, unpack them and replace the current "wine" folder in Flower Pot with new 32bit one. If it doesn't work, try the 64bit one.
If it still doesn't work, please try it with older version:
64bit: https://dl.winehq.org/wine-builds/macosx/i686/portable-winehq-devel-1.9.24-osx64.tar. gz
Please let me know how it went. Thanks and sorry for the inconvenience.