This was a long-standing bug since Luma3DS v8.0.
If you changed the homebrew title and didn't immediately reboot, then
the ExHeader during termination would not match the ExHeader that was
was used for loading the process, and thus sysmodule process refcounts
would get all messed up.
The obvious solution to this is to ensure no application is running
while changing the hbldr titleID (hence the changes in custom PM).
This was quite possibly one of the cause of homebrew failing to load
when using N3DS H&S.
