Well this site seems to have good information. They have a different emulator called trs80gp that runs on Linux. Also some interesting information here and here on copying a physical TRS-80 cassette tape to a virtual cassette or .cas file. I’d really like to retrieve a Yahtzee game I wrote. If I remember correctly I took advantage of TRS-80 graphics commands to roll the dice. A pretty big deal for this non-artistic programmer. The biggest problem I have is the emulator and cassette tool are both executables. I’d feel a little more comfortable if at least checksums were provided.