SIM990/DX10 help?

Hi everyone, I downloaded Dave Pitts' SIM990 emulator and the pre-rolled DX10 disk images available on his site yesterday evening, thinking I'd give it a run. SIM990 compiled clean; I'm running on Debian 7.7, 32-bit, on an Intel D510 Atom system. I feel as though this should be plenty of power... I run Hercules on this same system all the time to fool around with MTS and MVS 3.8J and I find the performance to be just fine... (way better than on my old Sun Fire V120s, LOL) I extracted the DX10 images and I started the emulator on them as directed: sim990 -msc 12 512K dx10.cfg For a terminal emulator, I'm using PuTTY; I also tried Procomm Plus (latest version) with a few different emulations and couldn't make it work, I seem to get furthest with PuTTY. I connect using Telnet protocol to port 2000 on the emulation host. I get the DX10 IPL screen: * TEXAS INSTRUMENTS * DX10 "SYS3 " SYSTEM IPL * ST01 I hit F10 then "!" and I get a sort of menu-like thing: **************************** DX10 3.7.0 THIS SYSTEM HAS THE FOLLOWING SUBSYSTEMS INSTALLED: COBOL PASCAL SORTMRG BASIC ... ***************************** I don't get a signon prompt but I assume user login has not been enabled on this basic disk image, however... I never get the SCI prompt, [], and it seems unresponsive; I've tried typing i.e. BASIC, COBOL, commands from the DX10 manual, totally random junk, etc. and I don't get any response; I mean, it seems to be refreshing the screen every time I hit RETURN; it's not giving me any kind of error message, but it's not really doing anything either. Is my emulation just not working right? I tried the DNOS image too and I was able to get a little further... At IPL it prompts for date and time which I'm able to fill in, and there is a login stage (l: SYSTEM, p: SYSTEM) which I can get through, just use the cursor keys to move through the fields and hit RETURN to push the screen (it seems screen-oriented, feels reminiscent of an IBM) but once that's done I land at an equally unresponsive main menu just like I describe occurring with DX10. Has anyone played with this and found a Telnet client that works well? I don't see anything on the author's site other than to note that Windows Telnet won't work. Not clear what I'm doing wrong. Thanks! Sean