Ah, you're right. When you said Amiga Forever I thought you mean the emulation it provides out of the box - which is AmigaOS3. Now I realized it also enables AmigaOS4 emulation if you provide your own AmigaOS4 files.
Anyway, both FlowerPot and Amiga Forever use the very same WinUAE emulator. Check whether there is the latest version in FlowerPot. If not, download 32-bit WinUAE ZIP archive from
www.winuae.net and copy the winuae.exe to FlowerPot (and overwrite the old executable there).
If it doesn't solve the issue then I think it must be something in the WinUAE configuration. You can compare the config used in Amiga Forever vs. the one in FlowerPot. I'll do that as soon as I get back from vacation.