There is no GSV protection in 35xx firmware so the firmware doesn't require patching. There is Map Signature Verification (MSV) protection in the firmware however so a map unlocker that doesn't overcome MSV in the required map won't work. Read the first several posts in [Only registered and activated users can see links. ] for the full explanation.

Which maps are you trying to use with ASR? Some countries don't have ASR files available for the maps and some won't work with partial maps and need the entire available mapping to be loaded, i.e. US/CA and Europe. More info on that here: [Only registered and activated users can see links. ].