what you have to add is ROM file and AmigaOS files. ROM files is NOT included with AmigaOS3.5 CD.
In your situation there are two solutions:
Use RomFind to locate and install the ROM automatically
Copy the amiga-os-310-a1200.rom and rom.keyfile from your AmigaForever C:\Users\Public\Documents\Amiga Files\Shared\rom\ folder to Portable AmiKit folder manually: Home/.wine/drive_c/AmiKit/ROMs Rename amiga-os-310-a1200.rom to kick.rom
Then use Amiga OS 3.5 CD to finish the installation according to the manual
When creating AmigaForever DVD, make sure only "Systems" content is enabled and all other items are disabled. This way you end up with about 350MB ISO image. Then follow the manual as linked above.