It seems indeed to be a scaling problem, with one of the fonts used by the game. I do not know of a way to solve this. Installing all fonts through Winetricks does nothing, changing dpi resolution in game or via wine cfg also does nothing....
This seems to be an issue with Vic's games' engines and WINE, as it also occurs with the other DC games (haven't tried ATG yet).
My guess is that it is something related to .NET framework, but...I would need some input from Vic...
After a bit more searching and reading, found the issue. I just had to add GDI+ via Winetricks, and now everything runs perfectly (except for the video tutorials that do not run inside the game, but can be played outside, of course).
So, to summarize:
DC:B runs perfectly fine with WINE on my iMac (running High Sierra OSx, with Wineskin 2.8.8, engine 3.21), with the following winetricks
>.Net 2.0 SP2
> gdiplus
Another game that does not need Windows ! [:D]
Regards
(Edit: the same winetricks are needed for the other Vic games, DC Case Blue, DC Blitzkrieg and ATG)