Currently there is no way to say what went wrong when you end up with a bunch of gray tiles and some rendered ones. There should be some kind of possibility to extend the current debugging info (layers styled, map rendered, icons/text rendered).
Things that would be helpful:
Tile number
Whether data needed for rendering has been downloaded successfully or not
Maybe this info can be added as a half transparent layer (so that info for each tile is shown inside that tile) that can be switched on when necessary.
Currently there is no way to say what went wrong when you end up with a bunch of gray tiles and some rendered ones. There should be some kind of possibility to extend the current debugging info (layers styled, map rendered, icons/text rendered).
Things that would be helpful: Tile number Whether data needed for rendering has been downloaded successfully or not
Maybe this info can be added as a half transparent layer (so that info for each tile is shown inside that tile) that can be switched on when necessary.