I have an issue with this as there does not appear to be any way of redirecting the download to an SD card. The files are many and substantial and I only have 16GB of storage. It is all very well to say that this is an Android problem but a fundamental and differentiating feature of the applications is the ability to use it off-line. This ability depends on being able to store off-line maps. If Android cannot do this effectively then the application is fundamentally flawed.
In addition there is a question regarding identifying the offline maps downloaded. Quite sensibly after you download a map it becomes available again for download but how can you identify the maps already downloaded - is there a list and where are they stored?