Today I will demonstrate what we do when something goes wrong or has to be fixed inside a blendfile! Recently we changed the way the armguns file works in order to make it more efficient (long story short: there used to be multiple proxies referring to multiple armatures, which were automatically generated with a script, and now the armature is the same and it is shared by the proxies).
How do we tell Blender that all the armatures have to be renamed to match a single one? Simple, we open up any hex-editor (such as bless) and look for the text to replace – in our case any ARrig_armgun* will become ARrig_armgun. Some attention must be payed in order to keep the file length consistent so that the file is not corrupted. This can be done by inserting empty spaces in substitution of the erased chars.
I hope this can be of any use to you all!