FRTS on PDP-8

I've been trying to get Colossal Cave Adventure (ADVENT.SV) running under OS/8 with no luck. A few details: I've got 32k of core in a PDP-8/M (the entire backplane is filled!) and am using my SerialDisk software for emulating an RK05. That software can be found here: https://github.com/drovak/os8diskserver David Gesswein pointed out at VCF East that my software doesn't disable interrupts on the card, which is required for FRTS. Thus, I'm running a three-line program to disable interrupts on the M8650 I'm using for the SerialDisk interface before starting OS/8. Symptoms of attempting to run ADVENT (RUN SD1 ADVENT, where SD1 points to the second partition on the diagpack2.rk05 image) are that it takes about 30 seconds before just returning back to the dot prompt. No errors or anything. Lots of disk activity, but it never really does anything. I've used a fresh image with ADVENT on it, so there shouldn't be any issues of the files getting moved on disk. I also can run it under simh with no issues whatsoever. I suspect there is an issue with my SerialDisk software, but I don't know where I should begin to debug it. This is the first incompatibility I've come across with the latest version. Anyone willing to check it out on another system to confirm an issue? I was hoping to show this off at the second annual Vintage Computer Festival Southeast, but at this rate, it's not looking good. The disk image is here: http://www.pdp8online.com/pdp8cgi/os8_html?act=dir;fn=images/os8/diagpack2.… Thanks! Kyle