Another thing to try - use the oldest version of Chimera - see http://www.tonymacx86.com/downloads.php?do=cat&id=8Best I've got is a 2Gb one. I'll give it a go and report back........
OK, if it went to desktop with no problem, then install Chimera 1.7 and reboot without the USB.Wooh! You were right, the old 2Gb stick booted fine first time. So that's booting with Chimera 1.7 no problem. What now though?