I tried to make the additions that I'd mentioned, but haven't been able to yet. But I did clean up the code a tad and rearrange parts of it a bunch-- without breaking it! -- so now it should be flicker-free.
I'm calling the current version 0.1, since I've decided that the initial flickering one was 0.0! Besides rearranging things a bit, I've replaced all single-letter variable names with more meaningful names, which should help anyone who is trying to read the code and figure out what I'm doing.
I also replaced the "seeing eye" on level 1 with a sling, but I haven't added any rock-throwing or rock-slinging yet. And when I sat down to add the varying mazes for level 1, I quickly realized that it won't work the way I've got things right now, so I won't be able to do anything on that until this weekend when I can reorganize the way the levels and rooms work.
I'll also be migrating the game to batari BASIC 0.35, which should help me make additional reorganization and improvements.
Fixing the flickering has also sped up the game, so be warned, because the hero moves faster, but so does the monster!