Sorry I don't know enough to be able to give you a complete answer but I'll try
to add what I know.

First, if by "data card" you mean USB flash drive, my experience has been that
writing to such a device by HTT is much, much slower that writing to an
internal hard drive.  I would suggest you first mirror to your local HDD and
then copy or move the mirror to your "E:" drive.  I would try doing that in a
new folder as a new project and see if it still crashes.

If it takes a long time but doesn't crash, the problem (of slowness) is
probably with the web server or the host throttling down bandwidth to your IP
address.

HTH,
~B^D