That's weird. There's a different error message when it can't assign it because it's already used by someone else, so that's not it. Can't think of why else that would happen. Can you look at the log file and see if there are any errors? The log file should be at C:\Users\<your name>\AppData\LocalLow\Total Fluke Studios\StripClubWars\Player.log
Do you still have the save file from 1.09? Can you look for scw00541 in it and see if it still assigned to the character in question?
Here are the errors for 00541, but there's a ton of these in the log for more IDs as well - 2696 lines total to be exact.
Code:
Invalid image file 'E:\Downloads\Games\StripClubWars\StripClubWars_1_10/characters\scw11\scw-00541-z1-fun.png' - either bad format or loose image with no master
Invalid image file 'E:\Downloads\Games\StripClubWars\StripClubWars_1_10/characters\scw11\scw-00541-z2-bc.png' - either bad format or loose image with no master
Invalid image file 'E:\Downloads\Games\StripClubWars\StripClubWars_1_10/characters\scw11\scw-00541-z3-s2.png' - either bad format or loose image with no master
Invalid image file 'E:\Downloads\Games\StripClubWars\StripClubWars_1_10/characters\scw11\scw-00541-z4-cas.png' - either bad format or loose image with no master
Invalid image file 'E:\Downloads\Games\StripClubWars\StripClubWars_1_10/characters\scw11\scw-00541-z8-tl.png' - either bad format or loose image with no master
I do still have the old save backed up, and the Person line for this character in the save has scw00541 assigned. If I open the save in 1.09 it works fine as well.
Edit: Out of curiosity I copied my complete 1.10 folder to a different drive letter, and for some reason most of the images are loading fine now, with only 27 lines of the 'either bad format or loose image with no master' error.
EditEdit: Honesty, you can probably ignore this 'bug' unless you're just curious. My E: drive is a software RAID 0 of multiple disks, and that seems to be somehow messing with how the files are loaded. When I swapped the folder to a RAID 1 instead, it suddenly loads without issue. Very weird stuff.