Guess we're reporting everything here.
If I try to just download a cIOS WAD, the hackmii installer is always downloaded (or at least it tries to download it, it's not actually downloaded, but the folder structure is created and the progress bar says it's being downloaded)
There is a GPL issue with how you're constructing cIOS WADs. In fact my first attempt to build cIOS WADs with ModMii did the exact same thing u are doing now, and I was forced to change it before releasing it publicly because it violates GPL.
Basically, u can't diffpatch an IOS wad to create a cIOS WAD. The WADs are encrypted, and therefore when u create diff files between 2 WADs, not all the similarities between the two can be found (cuz they're encrypted) and the diff files will contain encrypted nintendo code. This also explains why the size of your diff files are about 30x larger than the diff files I'm using (feel free to use mine if u want btw).
The proper way to do it is to unpack the base IOS, and diff patch the components (or hex edit them directly if u know the offsets, you can find a lot of the offsets is ciosmaps.xml included with d2x cIOS downloads). Since the components are not encrypted, similarities between the components can be found when creating the diff files and they will not contain any nintendo code (and should be smaller). You'll have more than one diff file per cIOS, but each one will be around only 1KB and applied very quickly.
I just want to make sure you understand I am not trying to say anything bad about your app, I just want to save you the GPL headaches I had to go through with ModMii.
Anyways, it's my nieces 1-yr bday today, I'll catch u later!