Thank you. I hope you will have a good trip down the memory lane and will enjoy the working game. I had fun testing, which is a good sign. And let me know when you struggle too much. There is always a way.
Please note that the checksum tool installs itself in the tape buffer area. Therefore only save to disk is supported. If you want to save to tape then use the following pokes to deactivate the checksum tool:
poke770,131:poke771,164:poke772,124:poke773,165
Before running the typed in program it is also strongly recommended to deactivate the checksummer (or better reset the computer) since the tape buffer may also be used by the program logic and without deactivation it may crash the computer.