I'll repeat, when I try to open the ips file it says: "Couldn't open file for reading"(+the location of the file).
When I try to patch it using the aps patch file, it says "the selected aps file is not a valid patch".
This is getting ridiculous. I really want to try out this hack...
I had the same problem, but was able to fix it.
I was recently playing PC games from Japan, and I had to change my system locale to Japanese so the games would work. Both the .ips and .aps files did not like that for some reason. When I changed my system locale to English(United States), they both worked fine. Perhaps this is your problem?