stopping by the forums this morning to scan for ideas as I'm redesigning the client ID/template system, and wanted to let you know I am thinking about this.
custom apps in dSS is a major area of concern for me, and I want to bring them up to speed to be compatible with d7II's system. unfortunately I already have plans to improve (aka CHANGE) d7II's custom apps system quite a bit to add some awesome new functionality, and I hate the thought of doing the work to update dSS, just so it will be obsolete again in a month or two. Now if that was all I had to do for dSS I would be doing it right now, but I strongly believe time now must be spent on the client ID/template system first, when that is complete I can focus on custom apps.
Once I do get around to custom apps, though I may rethink this in time, currently my plan of attack is actually to create a single binary to handle custom apps, so it isn't necessary to update two different apps to bring them both the same custom app improvement, and all custom apps between my apps are as close to 100% compatible as it will get (considering different usage scenarios, but at least in configuration SYNTAX and format.) So actually when I do this for d7II (or dSS) or whatever, it can simply be distributed to both apps without any changes before compile. Being that d7II has a newer code base than dSS for virtually everything already, I'll be pulling the custom apps code from the d7II binary for this project -- which means working with d7II, which isn't my goal right now -- it is dSSMC. Besides, I still need to consider a few things to really determine if this idea is the right decision, and the best way to proceed with a smooth transition if it is.
Either way, the actual point of this was to tell you that while no the current custom apps from d7II are not fully compatible with dSS (with regards to any functionality added in about the last year and a half I'm afraid) -- this will change! In the meantime expect to see some other great improvements to the management system sooner rather than later.