Lawrence Kesteloot has updated his amazing TRS-80 Tool cassette utility to v2.10. The change is the addition of a “–entry” option which will permit you to designate entry locations when disassembling a file. Since the disassembly routine logically determines when something is code and something is an ascii string, and shows the string if there is one; there was an issue when a program relocates itself. In that case, the disassembler routine assumed everything was ASCII because it wasn’t being executed. Now, if you get a bad disassembly, you can set an “–entry” option to tell the disassembly routine to start processing that location as code.
The standalone can be found on https://github.com/lkesteloot/trs80/tree/master/packages/trs80-tool. v2.10 can be downloaded there or right here for Windows / Linux / Mac.