What kind of files are uploaded to astrometry.net?. The raw fits files?. If this is the case, maybe it should be better to convert the image to a lossy format like jpeg (imagemagick?) and then upload the lossy image. I mean, for normal connections, 10 mb should take a while, while 100kb is almost instantaneous. And for solving an image, to have some small artifacts like in jpeg is not really a big issue.
By the way, I'm having some problems with this alignment tab using my DSLR images (fits). If I convert them to jpeg and then run directly solve-field, it takes a few seconds to solve the imagen. On the other hand, in kstars it never solves the image.
ok, I added an option to upload FITS as JPEG to astrometry.net, it is ON by default. Please update to kstars-bleeding and test. It works OK on simulation, but might need fine tuning.