I personally have not used the ALTASMI_PARALLEL megafunction so I may not be very useful there. However, what you have described seems very feasible to me and I don't see any problem with doing so. That is the purpose of the ALTASMI_PARALLEL megafunction after all is to allow you access to that memory.
I would ask however why you feel you need to try to load the application image more than once? My approach has always been that if it failed once, something is wrong and there is no reason to attempt to load it again until a new image has been loaded. You don't need to keep a count in order to do this. The status registers in the ALTREMOTE_UPDATE megacore will give you sufficient information to know that the application image failed. At which point you just sit and wait until your told through some external mechanism to try again.
Jake