Off-colours red (german Fehlfarben) of b/w photos

Nach dem Öffnen eines mit FM5.x erstellten Projekts erfolgt eine Fehlfarbendarstellung (extremes Rot) mehrerer SW-Fotos. Beim Klicken auf dieses Bild stürzt ab.

After opening a project created with FM5.x, there is a miscolor display (extreme red) of several b&w photos. When clicking on this image crash

Process: FotoMagico [83556]
Path: /Applications/
Identifier: com.boinx.FotoMagico6.macOS
Version: 6.0b21 (1013480)
Code Type: X86-64 (Native)
Parent Process: ??? [1]
Responsible: FotoMagico [83556]
User ID: 501

Date/Time: 2021-04-26 11:00:17.378 +0200
OS Version: macOS 11.2.3 (20D91)
Report Version: 12
Anonymous UUID: B80A776E-87DD-8330-A2D0-3174E2C27EE1

Sleep/Wake UUID: 5F3FB0D2-A15B-46BD-84A8-B6A8D8EC3DE8

Time Awake Since Boot: 810000 seconds
Time Since Wake: 1100 seconds

System Integrity Protection: enabled

Crashed Thread: 8 Dispatch queue:

Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000

Application Specific Information:
-[MTLTextureDescriptorInternal validateWithDevice:]:1248: failed assertion `Texture Descriptor Validation
MTLTextureDescriptor has invalid pixelFormat (11).

Update: I can provoke this crash by selecting the wrong color image and clicking in “Color Correction”