I cannot create a new GRIB File for the South Pacific if the right-hand side is east of longitude 180, and I want to customise settings. To reproduce:
1. Select Add GRIB File, Via Map
2. Select an area that covers New Zealand and extends east of New Zealand beyond longitude 180, e.g. to the Chatham Islands.
3. Tap the "Settings" cogs on the bottom toolbar
4. Tap "Save". You should see the following message: "Bounding Box Error The upper left corner longitude may not be larger than the longitude of the lower right corner".
It is possible to refresh files I had previously created, and it's possible to download the new GRIB area if I don't try and change the defaults first.