I had nearly 7000 maps in one directory.
I split the maps, about 3500 each into two directories. I'm able to access all maps in each of the two directories just fine.
In my opinion, the error message should be issued just once, stating that not all maps were loaded. Currently, the error message seems to pop up for every map loaded that exceeds an unspecified limit. For the original directory with nearly 7000 maps, I had to click or enter "CR" several hundred times and the maps could not be sorted by filename (thus some functional was lost in addition to the missing maps).
Thanks,
Sun Tzu Wu