I'm sorry that you are having these problems, but you must realize that all of them are due to size mismatches in your structures. I am not sure why you are using structures; it might be easier if you simply used matrix variables.
In any case, if you have a 1-by-241 variable and a 241-by-1 variable that you are trying to add, then you should convert both to the same size. There are many ways of converting vectors. If M is the 1-by-241 variable, you can convert it to a 241-by-1 variable in any of the following ways:
Use whichever you like.
MATLAB mathematical toolbox documentation