Our rule of thumb is to never use latches unless you specifically have to. Use seal in circuits for those purposes. There are times when latches are the only way, but they usually are difficult to troubleshoot and understand in a larger program. It is useful sometimes to complete a program in "small bites." Program a little functionality - get it to work. Then program the next bit of functionality. Try getting the up and down seal in circuits first-then modify for the rest of the functions.