To run the CDP18S020 Evaluation Kit emulator at least the UT4 system ROM file should be specified in the 'ROM' field (orange ellipse). Default the CDP18S020 ROM location is the CDP18S020 directory (located in the application data directory, see Directory and File Structure) and the default filename is 'ut4.bin'. To change the location use the 'ROM' button (yellow ellipse) to browse for the file, do the same to change the filename or type in a new file name in the text field (orange ellipse).
The binary, Intel hex and RCS Elf Emulator hex format are supported.