catymag--ah, I did not know about the JetMouse not useable on FID>2200; in any case, I take it you're suggesting I use gimgunlock+mapsigpatch on a locked (2016.20) img file and hope that Garmin 2.9 (and higher) for iOS will recognize it without noticing that there is no (valid) GMA and/or UNL file present for it? FYI--I loaded a pre-unlocked IMG file and tried to see if Garmin 2.9 would recognize it...no luck, even if I first remove the GMA and UNL files or just leave them there; apparently 2.9 is looking for those files since it keeps thinking that there are no maps loaded and asks me to download them.

I'll try your suggestion but if Garmin got smart and decided to code newer versions of their iOS app such that it must detect valid GMA and UNL files in order to work, then I think I may be SOL.