Adding an existing FX chain to the ProChannel currently requires that you right click on the PC, add the FX chain holder module, then right click in the FX chain and go fishing around in the general plug in menus for your presets.
Would be really handy to have a cascading menu that comes off the FX chain in the PC menu, that features only existing FX chain presets. So you could get to your FX chain modules more or less as quickly as any other PC module.