Eric Greenwell wrote:

Try opening the file in SeeYou, which supports that format. It might be
easier to analyze the error there.

I should elaborate: when I've had SUA file problems, Glide Navigator
would often choke on it, but SeeYou would attempt to display it anyway.
The bad airspace would be immediately obvious on map, allowing me to go
to the right place in the file and fix it.
--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA