When changing to a different model ( CPM1 -> CJ ) yuo just need to be careful of any conversion instructions that may get introduced. Confirm that the code is the same as the smaller processor
Be aware of the simulator in CX-One, it is not like a real PLC.
The scantime is not like the real “thing”, so use the simulator as a test tool to see about the program / functions works and nothing more.
I talk of experience where we used the simulator to test an advanced program, and it worked ok. When we tested the program in the real CPU, we had to change a lot due to the real scantime for the program in the CPU.
The CPU we where using for our project was the CJ1H-H CPU66, and the program had a lot of word data handling in table and the data handling was very time critical.