The CPM1A is a very basic block type PLC that is extremely easy to program.
The biggest problem you will have is that Omron memory is a broad open sheet that can be very cofusing to people that are used to having to type in %I. %Q etc. There is no need for that nonsense with Omron. Just type in the number - but you have to be aware of your memory map that is explained in the manual.
We Omrom users love it because it saves time and money just typing in the i/O number.