No, where the program has been designed for the UK and Irish market, there are no multi language options.  Though I once had a support call where i dialled in to the PC and Sage200 was in chinese, because the version of Windows and the settings meant that everything showed in that language.  It was a few years ago and i dont know if it would behave that way now, so maybe install it on a PC set up as Polish and have a look.  Not sure if it'd cause any issues though (Form sizes and whatnot.) The only other thing i can suggest is log it on the Ideas Hub.