Payslip Loading Formula

[storemandave]

I'm trying to create a payslip checker where you only have to imput your worktimes (start and finish) and it works out the hours at the appropiate shift allowance (ie. Mondays from 1am to 5am is 130%). There is also the added dificulty that if more than half the shift is worked at a higher rate the whole shift is paid at the higher rate

I attached the worksheet. If anyone could help it would be greatly appreciated.