This is what I got so far:

I have entered the following line at the command line (after copying the OS file into the same directory as the flasher, located at C:\Program Files (x86)\maemo\flasher-3.5>):

flasher-3.5 -F RX-44_DIABLO_5.2008.43-7_PR_COMBINED_MR0_ARM.bin -f -R

The response I got is the following:

flasher v2.5.2 (Sep 24 2009)

RX-44_DIABLO_5.2008.43-7_PR_COMBINED_MR0_ARM.bin: %m

No message about waiting for anything. My guess is this might be what they meant when they said this program is for the N900, not for the N810, am I correct?

I am downloading the Ubuntu iso image to try an USB stick install in the meantime.