Hi
the selection variable tradeout_net is effectively the cash-out figure on a given selection. You mention you are trading on one selection only, so this should be what you need.
If you are trading multiple selections in the same market, you need to update a user variable for the cash-out on all selections in the market. e.g:
trigger 1
set user variable, name: cash_out, value: 0, indiv. for each market, first matching selection, execute: 0.3
trigger 2
set user variable, name: cash_out, value: cash_out+tradeout_net, indiv. for each market, all matching selections, execute: 0.3
so user variable cash_out will hold an up-to-date value of the market "cash out" and you can apply your own conditions using this user variable:
e.g.
trigger 3
green up, ticks: -1, all matching selections, condition: selections trigger expression cash_out is greater than 10
also might be worth having a look at how unticking the green up option "against last matched bet" might help you, as this will green up all the bets on a selection.