Here is some idea: https://fxdreema.com/shared/HBgwoQHnc
This is I think exactly what you want, but I'm pretty sure you will not understand what is going on here: https://fxdreema.com/shared/NNuCCXO9d
I use one extra Variable to change the amount of pips that must be traveled, only because I can't find how to get the OpenPrice of the latest child-trade. And by "child-trade" I mean... you will see how you start with one trade and how each following trade is visually connected to the initial one. This is done by MetaTrader itself
I was also thinking about this, but something doesn't work with lot sizes: https://fxdreema.com/shared/dCa88msrb
90% of the first lot size is 0.9 if the lot size is 1. But the next order calculates 90% of 0.9, which is 0.81 (not 0.8). And when you reach lower levels the numbers deviate more and more. This is because each following lot size is % of the previous one, not of the first one