I've seen this a couple of times now, and it seems reliably reproducable. Not sure if it is the process or the program though.
Run Chess Assistant under wine. Export chess game to rtf-file and save Open file in Writer Insert graphic from saved file (png) Save as RTF = complete freeze Don't know if CA inserts something in the rtf file that shouldn't be there. But Writer chokes on this every time so far. If I save the file as odt then insert graphic from file Writer saves as expected. Regards, Martin S