OK, while experimenting with CHD files for PlayStation 1 Emulation and switching from Default to different cores I somehow broke it totally. Now every game goes back to ES with a blank screen OR locks up the whole system requiering either a Power Down or a REIBUS. I deleted the PSX entries for both beetle and mednafen in the config-file, but still no cigar. I had several games running fine, now resetting everything back to Default is not helping at all. Any hints whether there is any other config-file (like the one for VICE) that can break stuff here specifically? Everything else works.