I also got similar problems. On some old ISOs i had, i was actually successful on mounting the ISO by running the httpdisk.exe manually. Then I downloaded and created new ISOs from uupdump.net but was not able to mount the ISO manually at all.
These are the logs from the ISO I got to mount manually. It differs a little bit in vtoype.log from the never ISOs
These are the logs from the ISO I got to mount manually. It differs a little bit in vtoype.log from the never ISOs