Omega system takes about ten seconds to set up (and the Dev kit is FREE.) Same texture UUID that goes onto system layer goes into Omega script. There is no universal 'one template fits all'. For those heads which have different UV than the system avatar one needs to use the UV provided for the specific mesh head. Unfortunately some mesh heads use their own modified UV layout. The way I understand understand things is that the Robinwood template works well only on those mesh heads which use exactly that UV template (and naturally it works well with system avatar).
The OP said: 'What my plan is, is to use the BOM system, aka the classic avatar system to apply on both classic and mesh heads.'