You could take AddSix 02 and modify the logic to only trade EURCHF, GBPCHF and EURGBP and you'd have the Add_04.
The good results are partly due to using a bröker with tiny spreads. The downside with that bröker is that you have to pay a monthly fee. I tried the same EA with IBFX and it didn't open enough trades to be worthwhile. Big spreads on those pairs get in the way.
A good thing to keep in mind is that the policymakers, bankers and brökers over the last few years have added little annoying things to make it hard to do well as retail traders. Swap/interest rates were adjusted to keep us from accumulating swap money on certain pair combinations, same-pair hedging was eliminated unless you follow FIFO (or however it is now), ticks are heavily filtered to keep us from exploiting distortions, leverage has been decreased (probably good for the many clueless traders who haven't bothered to self-educate about margin, leverage, etc.), brökers adertise "low spreads" but freely increase them when it serves their purposes, brökers flag and disallow various trading styles and trade against our positions... and that's just a partial list.
Open to new approaches.