Hi Bruno,
first of all, make an image of your CF card so you can re-flash it later if anything goes wrong. You can use USB Image Tool for the job, for instance:
https://www.alexpage.de/usb-image-tool/download/Which Vampire do you have exactly? With which core? If it is an AROS core, be advised that AROS ROM is not 100% compatible with AmigaOS. While AmigaOS ROM can boot AmiKit CF card, the AROS ROM cannot. This is something that should be addressed by Apollo.
Anyway, if you have V4SA, you can map AmigaOS kick.rom from SD card when you power up your Vampire (you need to hold down right mouse button during power up). Please follow this link for more information:
https://www.amikit.amiga.sk/v4coresupport