Customisation of a woo-commerce addon plugin wordpress

Hi, I need a customisation for a plugin that acts as an addon to the standard woo-commerce plugin for wordpress. The plugin Custom Woocommerce Measure Price Calculator is a plugin that is used when customers need to enter custom measurements and based on the input the appropriate price is calculated for the product. Currently is has the functionality where the price can be set per sq units and depending on the sq units (length and width) entered the price would be calculated. Rather than this, I want a tier structure that: width<137 and length < 200 it should have price x1 225<width< 137 and length <220 it should have price x2 225 < width < 260 and length <220 it should have price x3 This should work with variable products and I should be able to set different price tiers for different product variables.