Many happy memories of checking out books like this from my public library and trying to get the programs working on the C64. The BASIC dialect never matched exactly.
A clever friend of mine wrote BASIC games that he sold back then. I think they had a bit of Z80 assembler built into it too.... Can't remember what names of them were though.
The 'hires' graphics mode (511*255, monochrome) were encoded into sprites. There were only 128 characters from memory. There were all sorts of tricks to try and get around that issue.
The best games used the sprites plonked into char positions.
It was a bit weird to program for, as you said the basic was not quite the same as the popular platforms. It did mean you learned a lot about the machine itself, how memory was laid out, how to get those PCG graphics right.
It’s funny now to be able to see very similar cultures sprang up around less successful machines in other countries.