These later cores have a number of issues for me, some of not related to 68020 updates, I believe:
* it requires "slow RAM" - if I try to use without, and just 24MB "fast RAM", the system boots (for hd image), but ends up with lots of "recoverable alert 0100 000C from 0005 05a0", it cannot read "pointer.prefs" (of all prefs), and it ends with full Ram Disk before it just reboots. Attempts to boot without startup-sequence just gives me a bright pink screen. I throw in a "set echo on" in the Startup-Sequence, and it seems like any access to RAM: leads to "0100 000C"
* with slow ram attached, it boots like normal, but display is not the same as it has been - the display is stretched wider, and with my overscan settings (PAL), both left and right edge vanish outside of displayed, visible area. In addition, if I blank the borders (using bblank, BoarderBlank etc), a huge chunk of the left side of Intuition screen area is also blanked. Normally, the border blank only affects areas outside of what is configured with Overscan.