I installed the PFP mod yesterday, and ended up losing a custom battle...

My Spanish army was as follows:
Six tercio pikemen.
Six musketeers.
Five dismounted conquistadores.
Three mounted conquistadores.

The French army was as follows.
Three aventuriers.
Three Scots guard.
Three voulgiers.
Three dismounted noble knights.
Four lancers.
Four gendarmes.

I stood my tercios in a single line, four deep, backed by two rows of two deep musketeers. I had one mounted conquistadore flanking on either end, with one in reserve, along with a dismounted conquistadore. I spread out my other four conquistadores so that they were spread between and behind a pair of tercios.

So... I sent in my flankers against the aventuriers immediately; they took out about half of them before they were overwhelmed and routed. Meanwhile, the French come in heavy on my left and try to sweep their lancers around my tercios, so I send my reserve units to that side. The majority of their infantry and cavalry end up being routed, at the loss of about 3/4 of my infantry, and all of my cavalry. All that remains is the French aventuriers and Scots guard... who proceed to rout every single one of my units...