Minor UEFI Booting Issue - Boot volume not available

I had the exact same problem yesterday after re-partitioning my disk to support EFI boot. Unfortunately I haven’t seen the reply above so I experimented by myself.

The only info I can provide that could maybe help is that I resolved it by putting the FAT32 EFI partition AFTER the Haiku one in the disk. Just because I noticed that USB stick was using the same layout and thought of trying it. USB stick was an older nightly I had around, hrev54945. Nothing else worked. So, this works in my case. But I noticed that if another external USB disk is attached then the problem appears again. All partition work was done with Drive Setup from USB stick.

Also not thought about checking boot loader log…